Casting installation for casting metal casting material and method for casting metal casting material

Description

[0001] The invention relates to a casting system for casting metallic casting material, wherein the casting system comprises a melt bath container for providing casting material in a liquid state, a casting device designed for injecting casting material into a mold of the casting device, and a metering container movable from the melt bath container to the casting device, in particular designed as a metering pipette, in order to take a meterable quantity of casting material from the melt bath container into a receiving chamber of the metering container and to dispense it to the casting device, wherein the metering container is coupled to an evacuation device of the casting system in order to evacuate the receiving chamber to create a vacuum in the receiving chamber in order to take in the quantity of casting material into the receiving chamber.

[0002] The invention further relates to a method for casting metallic casting material, wherein a metered quantity of casting material is taken from a melt bath container containing liquid casting material into a receiving chamber of the metering container by means of a metering container, in particular a metering pipette, or casting material in a solid state is placed into the receiving chamber, after which the metering container is moved from the melt bath container to a casting device, and casting material is dispensed from the receiving chamber to the casting device in order to press the casting material dispensed to the casting device into a mold of the casting device, wherein, when liquid casting material is taken up by the metering container for the intake of the quantity of casting material into the receiving chamber, the receiving chamber is evacuated by means of an evacuation device so that a negative pressure is formed in the receiving chamber.

[0003] Casting systems for casting liquid, metallic casting material are known, wherein a dosing pipette, usually movable by a robot arm, is used to extract a specific quantity of casting material from a crucible while evacuating the dosing pipette. The dosing pipette is then moved by the robot arm to a die-casting device, and the casting material is fed from the dosing pipette into a casting chamber of the die-casting device. The die-casting device is configured to inject the casting material supplied to the casting chamber into a mold of the die-casting device in order to produce a component by cooling the casting material in the mold. The purpose of the crucible is generally to provide a molten pool of liquid casting material.The purpose of the dosing pipette is typically to transfer a defined quantity of liquid casting material from the crucible to the die-casting unit and dispense it into the casting chamber, minimizing oxidation effects and material losses. This allows for the practical supply of a measured quantity of liquid casting material to the die-casting unit, enabling the production of components by injecting the liquid material into the mold.

[0004] Another type of casting system is that used for thixocasting, also known as semi-solid casting. In this process, liquid casting material is typically ladled from a crucible into a conditioning crucible. The material is then conditioned in the conditioning crucible to transform its liquid state into a thixotropic state. This conditioning usually involves cooling and stirring the material in the conditioning crucible, often with the aid of a stirring tool, to convert the material into a thixotropic or solid-liquid phase, typically through shearing. The material in the conditioning crucible usually forms a slurry-like consistency.The thixotropic casting material is then typically tipped from the crucible into a casting chamber of a die-casting machine. The die-casting machine is generally designed to inject the thixotropic casting material into a mold without turbulence. Die-casting systems designed for thixocasting can generally produce near-net-shape components with high precision. Compared to die-casting systems using liquid die-casting, thixotropic die-casting systems usually require a more complex process and a larger footprint.

[0005] Documents JP5919359, US9889494 and CN105583385 reveal exemplary casting plants in which liquid metal is transported in a crucible to the conditioning station.

[0006] This is where the invention comes in. The object of the invention is to provide a casting system of the type mentioned above, which has improved usability.

[0007] Furthermore, it is an objective of the invention to provide a method for casting metallic casting material of the type mentioned above, which has improved usability.

[0008] The object of the invention is achieved by a casting system of the type mentioned at the outset, if the casting system has a conditioning station with an induction unit, wherein the dosing container can be moved to the conditioning station with the dosing container before the casting material is dispensed to the casting device, in particular optionally, in order to stir the casting material electromagnetically with the induction unit in order to bring the casting material into a thixotropic state.

[0009] The invention is based on the idea of ​​using a casting system for liquid casting, based on a metering container movable from a melt bath container to a casting device, wherein the metering container is designed to receive a metered quantity of casting material into an evacuable receiving chamber of the metering container from the melt bath container, to implement thixotropic casting, in particular thixotropic die casting. In this way, a casting system for liquid casting can be used for thixotropic casting with reduced effort, in particular optionally. This is achievable if the metering container is used for conditioning the casting material. Conditioning usually refers to a treatment of the casting material to convert it, in particular from a liquid phase of the casting material, into a thixotropic phase of the casting material.It has been shown that a thixotropic phase of the casting material can be achieved by electromagnetic stirring of the casting material, particularly liquid material, in the receiving chamber. The dosing container is preferably a dosing pipette. If the casting system includes a conditioning station with an induction unit for electromagnetically stirring the casting material in the receiving chamber, a thixotropic state of the casting material can be achieved. The dosing container is typically movable to a conditioning position relative to the induction unit, in which the casting material in the receiving chamber can be electromagnetically stirred by the induction unit.This method allows the casting material to be drawn into the dosing container, particularly the receiving chamber, with reduced interaction with the surrounding atmosphere, especially with reduced oxidation effects. The material is then transferred to a thixotropic state and dispensed to the casting device via the dosing container. This results in a high operational efficiency of the casting system.

[0010] The melt bath container, which may be a crucible, for example, is typically designed to hold liquid casting material, usually as a melt bath, or to make it available for dispensing by the metering container. Typically, after receiving a measured quantity of casting material, the metering container can be moved from the melt bath container, and especially after electromagnetic stirring of the casting material in the receiving chamber, to the casting device by means of the induction unit, in order to dispense casting material from the receiving chamber to the casting device. The melt bath container and the casting device are usually separate objects and / or arranged at a distance from each other. The induction unit is typically controlled, especially regulated, such that a temperature and / or a solid-phase fraction of the casting material in the receiving chamber can be set by the induction unit.It has been shown that it is advantageous if the solid phase fraction is less than 20%, particularly between 0.1% and 20%, preferably between 1% and 15%, and most preferably between 3% and 10%. With such a solid phase fraction, particularly trouble-free handling of the thixotropic material is achievable, especially with regard to handling the dosing container when thixotropic material is present in the receiving chamber.

[0011] It is advantageous if the casting system has an electronic control unit for controlling, and in particular regulating, the casting process. This electronic control unit typically includes a microcontroller. The electronic control unit can be configured to control, and in particular regulate, the casting system, preferably automatically, and especially depending on the composition of the casting material.

[0012] The casting system typically includes a motion device with which the dosing container can be moved, preferably in a controlled or regulated manner. In particular, the dosing container can be moved by the motion device from the melt bath container to the conditioning station and / or to the casting unit. The motion device can be configured to move the dosing container along one or more axes of movement, preferably aligned orthogonally to each other. The motion device can, for example, be a swivel arm or a gantry robot. The dosing container is typically mechanically connected to the motion device, preferably in a detachable manner. The motion device can be controlled, preferably regulated, by the electronic control unit and can be coupled to it accordingly.

[0013] The dosing container typically has an evacuable receiving chamber so that a negative pressure is created in the receiving chamber when the chamber is evacuated using the evacuation device. It is usually provided that, to receive casting material, the casting material is drawn into the receiving chamber when the receiving chamber is evacuated. The dosing container, and in particular the receiving chamber, is typically designed such that casting material can be fed into the receiving chamber from a bottom surface of the dosing container, and / or casting material can be discharged from the receiving chamber via a bottom surface of the dosing container, and in particular the receiving chamber. Casting material can usually be fed into and / or discharged from a lower area, particularly a lowest area, of the receiving chamber.The dosing container is generally designed such that, when the receiving chamber is partially filled with casting material, an atmospheric volume, isolated from the surrounding environment, exists above the casting material. The evacuation device is typically connected to this atmospheric volume via a gas-conducting connection to remove gas from the atmospheric volume. It is advantageous for the evacuation device to be connected to the receiving chamber via a gas-conducting connection at its upper surface, particularly in the highest region of the receiving chamber. The receiving chamber is usually a cavity that can be closed by a sealing element of the dosing container. The receiving chamber is generally formed by walls that preferably enclose it substantially completely.Typically, the walls of the receiving chamber of the dosing container are formed, at least partially, and preferably substantially entirely, from a ceramic material. The dosing container can be designed to receive a metered quantity of liquid casting material into the receiving chamber by at least partial immersion of the dosing container into a liquid casting material or melt bath received from the melt bath container. The melt bath is usually composed of liquid casting material. It is advantageous if the dosing container has outer walls that are at least partially inert, so that inert sections of the outer walls can be immersed in the melt bath, particularly without substantial chemical reaction between the sections and the melt bath, in order to receive casting material from the melt bath with the dosing container.The outer walls of the dosing container are typically formed at least partially, and preferably substantially entirely, from a ceramic material. The dosing container is usually designed to receive liquid casting material into the receiving chamber, particularly from the melt bath container. The dosing container is also typically designed to dispense free-flowing, thixotropic casting material from the receiving chamber, particularly to the casting device, usually a casting chamber of the casting device.

[0014] The dosing container typically has a casting material opening for receiving casting material into the dosing container, particularly the receiving chamber, and / or for dispensing casting material from the dosing container, particularly the receiving chamber, via the casting material opening. Advantageously, the dosing container can be designed to supply casting material to the receiving chamber via the casting material opening and / or to dispense it from the receiving chamber via the casting material opening. The casting material opening is generally connected to the receiving chamber by a conduit for the casting material. The dosing container can have a controllable, particularly adjustable, closing device for closing and / or opening the casting material opening. The closing device can be controlled, particularly adjusted, by the control unit and, in particular, can be coupled to the electronic control unit accordingly.With the casting material opening open, casting material can be fed into the receiving chamber or dispensed from the receiving chamber via the casting material opening. In particular, with the casting material opening closed, the passage of casting material through the opening can be substantially prevented by the sealing element. The sealing element is preferably a sealing plug. Accordingly, it is advantageous if the dosing container has a casting material opening that can be sealed with a controllable sealing element, in particular a controllably movable sealing plug, in order to feed casting material into the receiving chamber via the casting material opening when it is open. The dosing container can expediently have several casting material openings.In particular, the dosing container can have a first casting material opening for receiving liquid casting material into the receiving chamber and a second casting material opening for dispensing flowable casting material. The first casting material opening and / or the second casting material opening can be configured as described for casting material openings. The first casting material opening and the second casting material opening can be opened and closed separately from one another, in particular controllably, preferably regulatingly, usually with one or more closing means, which closing means can be configured as described in this document. In particular, the first casting material opening and the second casting material opening can each have their own closing means to open and close the respective casting material opening.The dosing container can be designed for metered intake of casting material into the dosing container, in particular intake chamber, and / or for metered dispensing of casting material from the dosing container, in particular intake chamber.

[0015] To receive liquid casting material from the melt bath container with the dosing container, the casting material opening is preferably immersed in liquid casting material or melt bath supplied by the melt bath container, so that casting material, particularly from below the melt bath surface, can be drawn into the receiving chamber via the casting material opening. The dosing container is typically designed accordingly. In this way, oxidation effects can be efficiently reduced, and in particular avoided. It is advantageous if the casting material opening of the dosing container is arranged in a bottom area of ​​the dosing container, preferably facing downwards. This allows casting material to be practically drawn into the receiving chamber by immersing the bottom area, especially the casting material opening, in liquid casting material or a melt bath.It is advantageous if the dosing container is designed in such a way that, when the casting material opening is open, free-flowing casting material can automatically flow out of the receiving chamber. The dosing container can be controlled, in particular regulated, by the electronic control unit and, in particular, can be coupled to the electronic control unit accordingly.

[0016] The evacuation device typically includes a vacuum pump to evacuate the receiving chamber, in particular to create a negative pressure within it. Generally, with the casting material opening immersed in the melt bath, casting material can be fed into the receiving chamber through this opening while evacuating the chamber, specifically by creating a negative pressure. The evacuation device, particularly the vacuum pump, is typically connected to the receiving chamber via a gas-conducting evacuation line. Gas can be extracted from the receiving chamber via this evacuation line, specifically by suction from the evacuation device. The evacuation line preferably connects to the receiving chamber at its upper end. The evacuation device can be part of the metering container.The evacuation device can be configured to variably control, and in particular regulate, a negative pressure in the receiving chamber, especially when casting material is being drawn into the receiving chamber. A suction force acting on the casting material in the receiving chamber, specifically for drawing casting material into and / or dispensing it from the receiving chamber, can be controlled, and in particular regulated, by this negative pressure. The evacuation device can be controlled, and in particular regulated, by the electronic control unit and can be coupled to it accordingly.

[0017] It is advantageous if the casting system has a gas supply device to supply gas, particularly inert gas such as argon, to the receiving chamber. The gas supply can be controlled, especially regulated. The gas supply device can be connected to the metering container, especially the receiving chamber, via a gas supply line. The gas supply device can be controlled, especially regulated, by the electronic control unit and, in particular, coupled to the electronic control unit, especially for the transmission of control signals.

[0018] It is advantageous for the dosing container to have a fill level measuring device for determining the fill level, in particular the fill volume, of the receiving chamber with casting material. The fill level measuring device can be configured to measure the weight and / or fill level of the casting material in the receiving chamber. The fill level measuring device can be implemented with one or more measuring sensors. Immersion of the dosing container into a melt bath located in the melt bath container to receive casting material from the melt bath into the dosing container, in particular into the receiving chamber, can be contingent upon the fill level of the receiving chamber being determined by the fill level measuring device. The intake and / or discharge of casting material from the dosing container, in particular from the receiving chamber, can also be contingent upon the fill level of the receiving chamber being determined by the fill level measuring device.

[0019] It is practical for the receiving chamber to have a first receiving chamber segment with a cross-sectional area that tapers in the direction of the casting material discharge. The casting material opening is usually located downstream of the first receiving chamber segment in the direction of the casting material discharge. Advantageously, the first receiving chamber segment can open into the casting material opening or into a casting material channel that forms the casting material opening. The direction of the casting material discharge of the receiving chamber usually refers to the flow direction of the casting material within the receiving chamber when casting material is discharged from the receiving chamber via the casting material opening. The first receiving chamber segment can be located downstream of a second receiving chamber segment in the direction of the casting material discharge, with the second receiving chamber segment having a substantially constant cross-sectional area.For example, the second receiving chamber segment can be formed with cylindrical wall sections and / or the first receiving chamber segment can be formed with conical, in particular frustoconical, wall sections. The wall sections are usually part of the receiving chamber walls. Typically, the dosing container, in particular the receiving chamber walls and / or an outer surface, preferably a shell surface, of the dosing container, is predominantly, in particular essentially, made of ceramic material.

[0020] It is practical if the casting material opening is formed by a casting material channel, which is connected to the receiving chamber by means of a casting material conduit. Casting material can be supplied to and / or discharged from the receiving chamber via the casting material channel. The casting material channel typically has an average cross-sectional area through which the casting material can flow, which is smaller than the average cross-sectional area of ​​the receiving chamber, particularly of the receiving chamber segment. The cross-sectional area of ​​the receiving chamber, particularly of the receiving chamber segment, is typically oriented orthogonally to the casting material discharge direction of the receiving chamber. The casting material channel is typically connected to the receiving chamber at one of its undersides by means of a casting material conduit.The casting material channel and / or the casting material opening can be formed by a tubular nozzle of the dosing container, which nozzle projects from a base body of the dosing container, particularly downwards. The receiving space is usually located predominantly, preferably substantially, within the base body of the dosing container. It is advantageous if the nozzle has a tapered outer diameter in a discharge direction. The discharge direction usually refers to the direction in which the nozzle projects outwards from the base body. Typically, a longitudinal extension of the nozzle is oriented parallel to the discharge direction. The discharge direction is preferably downwards. "Downwards" usually refers to the direction in which the dosing container is at least partially immersed in a liquid casting material or melt bath to receive the casting material.

[0021] It is advantageous if the metering container is designed for dispensing free-flowing, thixotropic casting material, particularly to the casting device. It is beneficial if the metering container is designed to dispense free-flowing metallic casting material, especially thixotropic casting material, with a solids content of more than 0.1%, particularly between 0.1% and 20%, preferably between 1% and 15%, and most preferably between 3% and 10%, from the receiving chamber to the casting device, typically via the casting material opening. This allows casting material in a thixotropic state with such a solids content to be dispensed from the metering container to the casting device with minimal interference. In particular, a suitable design of the casting material opening, especially the casting material channel, is necessary for dispensing casting material with such a solids content from the receiving chamber.This is of particular relevance because otherwise blockages with thixotropic casting material can occur in the dosing container, especially in the area of ​​the casting material opening.

[0022] It is advantageous if the casting material opening can be controlled, and in particular regulated, in such a way that flowable metallic casting material with a solid phase content of more than 3%, preferably between 3% and 20%, and particularly preferably between 3% and 15%, can be discharged from the receiving chamber to the casting device via the casting material opening. The casting material opening can be controlled, and in particular regulated, by the electronic control unit.

[0023] It is advantageous if the ratio of the average diameter of the receiving chamber to the diameter of the casting material opening is 2 to 15, particularly 3 to 12, preferably 5 to 10, and most preferably 5 to 8. This allows for trouble-free handling of the thixotropic material in the dosing container while simultaneously reducing oxidation effects. The diameter of the receiving chamber is usually measured perpendicular to the direction of the casting material discharge from the receiving chamber. The diameter of the casting material opening is also usually measured perpendicular to the direction of the casting material discharge from the casting material opening, in which the casting material flows when casting material is discharged from the receiving chamber via the casting material opening.The casting material discharge direction of the receiving chamber usually refers to a flow direction of the casting material in the receiving chamber when casting material is discharged from the receiving chamber via the casting material opening.

[0024] The induction unit typically defines a treatment receptacle into which the dosing container for electromagnetic stirring of the casting material can be at least partially inserted, such that the dosing container is at least partially surrounded by the induction unit. It is advantageous if the treatment receptacle and the dosing container are shaped to correspond with each other. The treatment receptacle usually defines the conditioning position of the dosing container. The dosing container is generally inserted into the treatment receptacle, specifically the conditioning station, in a non-contact manner. The dosing container is typically inserted into the treatment receptacle along with the movement device.

[0025] Preferably, the induction unit is formed with one or more inductors, in particular induction coils. The inductors typically define the treatment area. The respective inductor can be an induction coil having several coil windings. The electromagnetic induction field is typically generated by means of an electric current flowing through the coil windings. An area encompassed by the coil windings typically defines the treatment area. The coil windings are generally arranged on the surface of a body of revolution, for example, a cylinder or a cone. For example, the induction unit can be formed by a cylindrical induction coil having several coil windings, wherein an area encompassed, and in particular enclosed, by the coil windings is the treatment area.The inductors are generally designed to generate an electromagnetic induction field to electromagnetically stir the casting material in the receiving chamber when the dosing container is in its conditioning position. The stirring of the casting material is typically intended to cause shearing of the material, thereby inducing a thixotropic state, particularly with a defined solid-phase fraction. It is advantageous if the induction unit is designed such that, in the conditioning position, the dosing container is enclosed by the induction unit in all directions orthogonal to the insertion direction of the dosing container into the treatment receptacle.

[0026] It is advantageous if the dosing container can be inserted into the treatment receptacle in such a way that at least 20%, particularly at least 50%, preferably at least 65% of the volume of the receptacle is located within the treatment receptacle. This allows for the efficient adjustment of a specific solid-phase fraction of the casting material within the receptacle. It is particularly advantageous if at least 75%, particularly at least 85%, preferably at least 90% of the volume of the receptacle is located within the treatment receptacle. In particular, essentially the entire receptacle can be located within the treatment receptacle. In this way, the transition of the casting material to the thixotropic state can be controlled, and in particular regulated, with high precision.

[0027] It is preferred that the dosing container can be inserted into the treatment receptacle, particularly in a controlled manner, preferably with regulation, such that at least 20%, particularly at least 50%, preferably at least 65% of the filling volume of the receptacle is located within the treatment receptacle. This allows for the efficient adjustment of a specific solid-phase fraction of the casting material within the receptacle. It is particularly advantageous if at least 75%, particularly at least 85%, preferably at least 90% of the filling volume of the receptacle is located within the treatment receptacle. In particular, substantially the entire filling volume of the receptacle containing casting material can be located within the treatment receptacle. The filling volume of the receptacle refers to the volume of the receptacle occupied by casting material. The filling volume can be expediently determined using the fill level measuring device.In this way, the transition of the casting material into a thixotropic state can be controlled, and in particular regulated, with exceptionally high precision. Insertion into the treatment receptacle can also be controlled, and in particular regulated, typically depending on the filling volume of the receptacle. This can be achieved using the electronic control unit.

[0028] Typically, a control system, particularly a regulation system, allows the conditioning station, especially the induction unit, to set a specific temperature and / or solids content in the casting material within the receiving chamber during the conditioning position of the dosing hopper. Usually, in the conditioning position of the dosing hopper, the casting material in the receiving chamber is cooled and / or actively cooled to achieve a thixotropic state, particularly concurrently with electromagnetic stirring of the casting material. The conditioning station, especially the induction unit, can be controlled, particularly regulated, by the electronic control unit and can be coupled to it, typically via an electrical control line.

[0029] It is advantageous if the conditioning station includes a cooling device that allows the casting material in the receiving chamber to be cooled when the dosing container is moved to the conditioning station or when the dosing container is in the conditioning position, particularly in parallel with the electromagnetic stirring of the casting material by the induction unit. This allows the thixotropic state of the casting material to be achieved particularly efficiently. Cooling with the cooling device can be controlled, and in particular regulated, usually by the electronic control unit. The cooling device can be formed with one or more cooling elements through which a cooling liquid flows, which are preferably arranged and designed such that they surround the dosing container at least partially when the dosing container is moved to the conditioning station or when it is in the conditioning position.The cooling elements can be cooling channels, which can be designed particularly as part of a cooling circuit.

[0030] Advantageously, the induction unit can be designed to be movable, allowing it to move partially with the dosing container. This enables conditioning, particularly electromagnetic stirring, of the casting material in the receiving chamber while the dosing container is moving. This movement is possible when the dosing container is at least partially inserted into the treatment receptacle. This allows for high efficiency. The induction unit can be moved by a motion device of the casting system, preferably a controlled, and preferably regulated, motion device. The motion device can be implemented as part of the movement mechanism. Alternatively, it may be advantageous for the induction unit to move passively with the dosing container, for example, by implementing a mechanical connection between the dosing container and the conditioning station, particularly the induction unit.The mechanical connection can be controlled, in particular regulated, activated or deactivated.

[0031] The casting device typically has a casting chamber into which the casting material is fed via a dosing container. The casting mold of the casting device is usually located downstream of the casting chamber, so that the casting material can be pressed from the casting chamber into the mold by means of a pressing element, in particular a press piston. The casting device is typically a die-casting device and / or a forming device, in particular a drop forging device. The casting device can be controlled, in particular regulated, by the electronic control unit and can be coupled to it accordingly.

[0032] The control, in particular regulation, of the dosing container, the moving device, the conditioning station, and / or the casting device can each be achieved by a separate electronic control unit, which is typically part of the casting system. The dosing container, the moving device, the conditioning station, and / or the casting device can be connected to the electronic control unit for the transmission of control signals, generally via electrical control lines.

[0033] The object of the invention is achieved according to the invention by a method for casting metallic casting material of the type mentioned above, in which the dosing container is moved, in particular optionally, to a conditioning station with an induction unit before the casting material is dispensed to the casting device, after which the casting material in the receiving chamber is electromagnetically stirred by the induction unit in order to convert the casting material into a thixotropic state. The method can be implemented with the casting system described in this document. By using the dosing container for conditioning, whereby the casting material in the receiving chamber of the dosing container is converted into a thixotropic state, efficient, in particular optional, casting of thixotropic casting material can be implemented. In this way, a high degree of usability can be achieved.Typically, after the casting material has been brought into a thixotropic state in the receiving chamber, it is dispensed from the dosing container to the casting device, whereupon the thixotropic material is injected into the mold of the casting device. This injection process is usually turbulence-free. The dosing container is typically a dosing pipette designed to draw liquid casting material into the pipette or its receiving chamber under vacuum.

[0034] Preferably, the dosing container is used to draw liquid casting material, particularly in metered quantities, from a melt bath container into a receiving chamber of the dosing container. Alternatively, usually for smaller and / or more expensive quantities of casting material, it can be advantageous to feed the casting material in a solid state, typically as lump pieces, into the receiving chamber of the dosing container, usually in a metered quantity. Generally, when drawing liquid casting material into the dosing container and / or when drawing casting material in a solid state into the dosing container, the receiving chamber is evacuated by the evacuation device to create a negative pressure within the receiving chamber.

[0035] It is advantageous, particularly if, in a first process step, the casting material in the receiving chamber is converted to a thixotropic state by the conditioning station and the thixotropic casting material is then dispensed to the casting unit via the dosing hopper, or alternatively, in a second process step, the casting material in the receiving chamber is not converted to a thixotropic state by the conditioning station, but is instead dispensed in liquid form from the dosing hopper to the casting unit. Typically, the casting material dispensed to the casting unit is injected into a mold. In the first process step, the casting material is usually injected into the mold from the casting unit in a thixotropic state. In the second process step, the casting material is usually injected into the mold from the casting unit in a liquid state.The first and second process steps can each be implemented as described in this document. The casting system can be configured to carry out the first and / or second process step. The first and second process steps can take place sequentially. In the first process step, and particularly in contrast to the second process step, the dosing container is not usually moved to the conditioning station or into the conditioning position for electromagnetic stirring of the casting material in the receiving chamber. The first and second process steps can be carried out with different casting molds of the casting system. The first and second process steps can have the same or different compositions of the casting material.Advantageously, the casting system can have several melt bath tanks, with the dosing tank being movable to different melt bath tanks to receive casting material from the respective melt bath tank. It is advantageous if casting material with different compositions, particularly different melt bath compositions, is received or provided in different melt bath tanks, usually in a liquid state or as a melt bath.

[0036] The process for casting metallic casting material can be designed according to the characteristics and effects described in this document, particularly in connection with a casting plant. The same applies to the casting plant with regard to the process.

[0037] It is advantageous if the conditioning station allows the solid phase fraction of the casting material in the receiving chamber to be set between 0.1% and 20%, particularly between 1% and 20%, and preferably between 3% and 15%. With such a solid phase fraction, particularly trouble-free handling of the thixotropic material is possible, especially with regard to handling the dosing container when thixotropic material is present in the receiving chamber.

[0038] It is advantageous if the casting material in the receiving chamber is actively cooled concurrently with electromagnetic stirring to bring it into a thixotropic state. This allows for particularly efficient implementation of the thixotropic state of the casting material in the receiving chamber. This can be achieved using a cooling unit in the conditioning station.

[0039] It is advantageous if the casting system is automatically controlled, particularly regulated. This can be implemented with an electronic control unit specifically designed for this purpose. The control, particularly regulation, can be dependent on the quantity and / or composition of the casting material. It is especially advantageous if the conditioning station, particularly the induction unit, is automatically controlled, particularly regulated, depending on the material composition, particularly the alloy composition, of the casting material, in order to establish a thixotropic state of the casting material, particularly with a predefined solids content. The electronic control unit can be designed for this purpose. This can be implemented efficiently because a high degree of reproducibility can be achieved by using the dosing hopper for conditioning.In particular, oxidation effects can usually be neglected and / or the receiving space, which is generally largely isolated from the environment, allows for precise control of the conversion of the casting material in the receiving space into the thixotropic state.

[0040] The casting material is typically a metal alloy, in particular a light metal alloy. Preferably, the casting material is a magnesium-based alloy, an aluminum-based alloy, or a copper-based alloy.

[0041] Liquid casting material typically refers to casting material at a temperature above its liquidus temperature. Thixotropic casting material typically refers to casting material in a semi-solid state or at a temperature between its liquidus and solidus temperatures. Generally, the melt bath container, conditioning station, casting device, and dosing container are separate components and / or spaced apart from one another.

[0042] Further features, advantages, and effects of the invention will become apparent from the following description of an exemplary embodiment. The drawings referred to therein show: Fig. 1 a schematic representation of the casting plant; Fig. 2 und Fig. 3 Microscopic images show the material structure of components produced with the casting system, both with and without the use of a conditioning station of the casting system.

[0043] In Fig. 1 The diagram schematically depicts a casting plant 1 or a process for casting metallic casting material. The casting plant 1 comprises a melt bath vessel 2, a conditioning station 3, a casting device 4, and a metering container 5 movable by a movement device 6. Fig. 1 The diagram shows the interaction states of the dosing container 5 with the melting vessel, the conditioning station 3, and the casting device 4. The melting vessel 2 is designed to receive and supply liquid casting material. The dosing container 5 can be moved from the melting vessel 2, and optionally, to the conditioning station 3 and the casting device 4 by means of the movement device 6. The movement device 6 can, for example, be a swivel arm. The dosing container 5 is designed to receive a quantity of liquid casting material from the melting vessel 2 into a receiving chamber 8 of the dosing container 5. The movement device 6 then moves the dosing container 5, and optionally, to the conditioning station 3. There, the casting material in the receiving chamber 8 is electromagnetically stirred by an induction unit 7 of the conditioning station 3 to transition the casting material from a liquid state to a thixotropic state.The electromagnetic stirring typically takes place while the casting material cools in the receiving chamber 8. Subsequently, the dosing container 5, with its movement device 6, can be moved towards the casting unit 4 to dispense the thixotropic casting material from the receiving chamber 8 to the casting unit 4, usually a casting chamber 9 of the casting unit 4. The casting material dispensed to the casting chamber 9 can then be pressed into a mold of the casting unit 4 by a pressing element 10, in particular a press piston, to produce a component as the casting material cools in the mold. The dosing container 5 is coupled to an evacuation device 11, which allows the receiving chamber 8 to be evacuated, thus creating a vacuum in the receiving chamber 8 for the intake, in particular suction, of casting material into the receiving chamber 8.The evacuation device 11 is typically connected to the receiving chamber 8 via a gas-conducting evacuation line 12 in order to evacuate the receiving chamber 8 via the evacuation line 12. The metering container 5 usually has a casting material opening 13 connected to the receiving chamber 8 for receiving casting material via the casting material opening 13 into the receiving chamber 8 and / or for dispensing casting material from the receiving chamber 8 via the casting material opening 13. It is usually provided that the casting material opening 13 is immersed in liquid casting material located in the melt bath container 2 in order to receive casting material via the casting material opening 13 into the receiving chamber 8.In this way, a metered quantity of casting material can be taken up with the metering container 5 under reduced oxidation effects and subsequently, the metering container 5 can be used, in particular optionally, for casting liquid casting material with the casting device 4 or for casting thixotropic casting material with the casting device 4.

[0044] The induction unit 7 is generally formed with an induction coil comprising several coil windings. The induction coil forms a treatment receptacle into which the dosing container 5 can be at least partially inserted to electromagnetically stir the casting material in the receiving chamber 8. It is practical if the dosing container 5 is inserted into the treatment receptacle such that at least 20% of the volume of the receiving chamber 8, preferably at least 20% of the filling volume of the receiving chamber 8 with casting material, is located within the treatment chamber. In this way, a specific, and in particular predetermined, solid-phase fraction in the casting material can be set in a thixotropic state.

[0045] To dispense the thixotropic casting material from the receiving chamber 8 to the casting device 4, the thixotropic casting material is dispensed via the casting material opening 13 to the casting device 4, in particular its casting chamber 9. For this purpose, it is advantageous if the ratio of the average diameter of the receiving chamber 8 to the diameter of the casting material opening 13 is between 2 and 15. Alternatively, preferably cumulatively, it is advantageous if the thixotropic casting material with a solid phase content of more than 3%, in particular between 3% and 20%, is dispensed from the receiving chamber 8 to the casting device 4 via the casting material opening 13. In this way, trouble-free operation can be achieved when handling, in particular dispensing, the thixotropic casting material with the metering container 5.

[0046] Fig. 2 und Fig. 3 Microscopic images of a material structure from casting plant 1 of the Fig. 1 The microscopic images show an exemplary material structure of components manufactured with and without the use of conditioning station 3 of the casting system 1. Components are produced using an Al-Si7 alloy as the casting material with the casting system 1. Fig. 2 shows a material structure of a component which is produced without the use of the conditioning station 3, i.e. by injecting liquid casting material into the mold with the casting device 4.

[0047] Fig. 3 Figure 3 shows the material structure of a component produced using conditioning station 3. This involves converting the casting material in receiving chamber 8 into a thixotropic state, where a solid-phase fraction of 5% is converted, and subsequently pressing the thixotropic casting material into the mold using the casting device 4. The microscopic image of the Fig. 2 A dendritic grain structure is evident. In contrast, the image shows... Fig. 3 A globular grain structure is evident.

[0048] If liquid casting material can be drawn into an evacuable receiving chamber 8 of the dosing container 5 using a dosing vessel 5, and the casting material in the receiving chamber 8 is then electromagnetically stirred by an induction unit 7 of a conditioning station 3 in the receiving chamber 8 to convert the casting material from a liquid state to a thixotropic state, and subsequently the thixotropic casting material is dispensed to a casting device 4 for placement in a mold, thixotropic casting or a component manufactured by thixotropic casting can be implemented with minimal effort and reduced oxidation effects. In particular, the casting system 1 can be used, optionally, for casting with liquid casting material and / or casting with thixotropic casting material. This enables the implementation of a casting system 1 with high operational capability.

Claims

1. A casting installation (1) for casting metallic casting material, wherein the casting installation (1) has a melt pool container (2) for providing casting material in a liquid state, a casting device (4), designed for forcing casting material into a casting mould of the casting device (4), and a dosing container (5), which can be moved from the melt pool container (2) to the casting device (4) and is in particular designed as a dosing pipette, in order to take up, using the dosing container (5), a dosable amount of casting material from the melt pool container (2) into a receiving space (8) of the dosing container (5) and deliver it to the casting device (4), wherein the dosing container (5) is coupled to an evacuation device (11) of the casting installation (1) in order to evacuate the receiving space (8) using the evacuation device (11) to form a negative pressure in the receiving space (8) for taking up the amount of casting material into the receiving space (8), characterised in that the casting installation (1) has a conditioning station (3) with an induction unit (7), wherein, before casting material is delivered to the casting device (4) using the dosing container (5), the dosing container (5) can be moved, in particular selectively, to the conditioning station (3), in order to agitate the casting material electromagnetically using the induction unit (7) to transform the casting material into a thixotropic state.

2. The casting installation (1) according to Claim 1, characterised in that the dosing container (5) has a casting material opening (13), which can be closed using a controllable closing means, in particular a closing stopper, in order to supply casting material to the receiving space (8) via the casting material opening (13) when the casting material opening (13) is open.

3. The casting installation (1) according to Claim 2, characterised in that the casting material opening (13) of the dosing container (5) is arranged in a bottom region of the dosing container (5).

4. The casting installation (1) according to Claim 2 or 3, characterised in that the casting material opening (13) is formed by a tubular nozzle of the dosing container (5), which nozzle protrudes from a main body of the dosing container (5).

5. The casting installation (1) according to one of Claims 1 to 4, characterised in that the dosing container (5) is designed to deliver flowable metallic casting material with a solid phase fraction of more than 0.1 %, in particular between 0.1 % and 20 %, preferably between 1 % and 15 %, in particular preferably between 3 % and 10 %, from the receiving space (8) to the casting device (4).

6. The casting installation (1) according to one of Claims 1 to 5, characterised in that the induction unit (7) defines a treatment receptacle into which the dosing container (5) can be at least partially inserted so that the dosing container (5) is surrounded by the induction unit (7), at least in some portions, for electromagnetic agitation of the casting material in the receiving space (8).

7. The casting installation (1) according to Claim 6, characterised in that the induction unit (7) is formed with one or more inductors, in particular induction coils, wherein the inductors define the treatment receptacle.

8. The casting installation (1) according to Claim 6 or 7, characterised in that the dosing container (5) can be inserted into the treatment receptacle such that at least 20 %, in particular at least 50 %, of a volume of the receiving space (8) is inside the treatment receptacle.

9. The casting installation (1) according to one of Claims 1 to 8, characterised in that the conditioning station has a cooling device with which the casting material in the receiving space (8) can be cooled, in particular simultaneously with the electromagnetic agitation of the casting material using the induction unit (7), when the dosing container (5) is guided to the conditioning station.

10. The casting installation (1) according to one of Claims 1 to 9, characterised in that the cooling device is formed with one or more cooling elements through which a cooling liquid can flow and which are preferably arranged and designed such that they surround the dosing container (5), at least in some portions, when the dosing container (5) is in a position guided to the conditioning station.

11. The casting installation (1) according to one of Claims 1 to 10, characterised in that the induction unit (7) is movable so that the induction unit (7) can be moved partially with the dosing container (5).

12. A method for casting metallic casting material, wherein, from a melt pool container (2) of liquid casting material, a dosing container (5), in particular a dosing pipette, is used to take up a dosed amount of casting material into a receiving space (8) of the dosing container (5), or casting material in a solid state is put into the receiving space (8), after which the dosing container (5) is moved from the melt pool container (2) to a casting device (4), and casting material is delivered from the receiving space (8) to the casting device (4) in order to force the casting material delivered to the casting device (4) into a casting mould of the casting device (4) using the casting device (4), wherein, when liquid casting material is taken up using the dosing container (5) in order to take up the amount of casting material into the receiving space (8), the receiving space (8) is evacuated using an evacuation device (11) so that a negative pressure is formed in the receiving space (8), characterised in that, before the casting material is delivered to the casting device (4), the dosing container (5) is moved to a conditioning station (3) with an induction unit (7), after which the casting material in the receiving space (8) is electromagnetically agitated using the induction unit (7) in order to transform the casting material into a thixotropic state.

13. The method according to Claim 12, characterised in that a solid phase fraction of the casting material in the receiving space (8) is set between 0.1 % and 20 % using the conditioning station (3).

14. The method according to Claim 12 or 13, characterised in that the casting material in the receiving space (8) is actively cooled simultaneously with the electromagnetic agitation in order to transform the casting material into the thixotropic state.

15. The method according to one of Claims 12 to 14, characterised in that the conditioning station (3), in particular the induction unit (7), is controlled, in particular regulated, in an automated manner depending on a material composition of the casting material in order to set a thixotropic state of the casting material, in particular with a predefined solid phase fraction.

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