Apparatus and method for producing at least one metal component

Abstract

The present invention relates to an apparatus (1) for producing at least one metal component (2) by injecting a flowable, in particular thixotropic, metallic casting material into at least one cavity (4) of a multi-part mold (3), the apparatus comprising, arranged downstream in sequence, a conveyor device (5) for the flowable metallic material, in particular a distributor unit (6) embodied as a hot runner system, and the multi-part mold (3), the distributor unit (6) having an inlet channel connected to the conveyor device (5) and a plurality of outlet channels, each with an outlet nozzle (9), whereby the casting material supplied under pressure through the distributor inlet channel can be injected through the outlet nozzle (9) into the at least one cavity (4) of the mold (3) so as to simultaneously fill the at least one cavity (4) with casting material through the outlet nozzle (9). In order to manufacture components with high quality and high process reliability, it is provided that at least one of the outlet channels (8) is connected to the mould (3) in a sliding manner to allow a relative movement between the outlet nozzle (9) of the outlet channel (8) and the mould (3).Furthermore, the invention relates to a method for the corresponding manufacture of components (2).

Description

[Technical Field]

[0001] The present invention relates to an apparatus for producing at least one metal component by injecting a flowable, in particular thixotropic, metal casting material into at least one cavity of a multi-part mold, the apparatus comprising, arranged downstream in sequence, a conveyor device for the flowable metal material, in particular a distributor unit embodied as a hot runner system, and the multi-part mold, wherein the distributor unit has an inlet channel connected to the conveyor device and a plurality of outlet channels, each with an outlet nozzle, whereby the casting material supplied under pressure through the distributor inlet channel can be injected through the outlet nozzle into at least one cavity of the mold so as to simultaneously fill at least one cavity with the casting material through the outlet nozzle.

[0002] The present invention further relates to a method for producing at least one metal component, characterized in that a flowable metal casting material is guided under pressure from a conveyor device through a distributor unit to a multi-component mold to produce the metal component, the casting material is guided through at least one inlet channel of the distributor unit to multiple outlet channels of the distributor unit, and is injected into at least one cavity of the mold through an outlet nozzle of the outlet channel to simultaneously fill at least one cavity with the casting material through the outlet nozzle, and at least one of the outlet channels is connected to the mold in a sliding manner to allow relative movement between the outlet nozzle of the outlet channel and the mold. [Background technology]

[0003] From the prior art, devices based on which a liquid metal is poured into a mold cavity and solidified are known, and in particular die casting devices and methods have proven effective, which allow cost-effective production due to high process speeds and short cycle times.

[0004] Thixomolding or thixoforming has also become known as a further practical method, particularly for producing near-net-shape components, in which a metal casting material, typically an Mg-based alloy, is brought into a thixotropic state, typically within a temperature range between the solidus and liquidus temperatures of the casting material, usually with a shear load on the casting material, and in this state is pressed under pressure through a nozzle using a conveying device into a mold cavity. In this way, components can be produced with high precision and quality. However, preparing, feeding, and pressing the material in a thixotropic state into a mold usually requires complex process control and longer cycle times.

[0005] To reduce the formation of casting defects during the injection of thixotropic casting material, it is known to simultaneously fill cavities through multiple casting material supply channels that connect to the casting chamber at different locations. For this purpose, a distributor unit is used with multiple outlet channels or runners, through which the casting material is simultaneously injected into the cavities using nozzles. The distributor unit distributes the casting material, which is usually supplied at high temperature and under high pressure, to the multiple runners in such a way that the distributor unit is heated to a branching point where it branches into the multiple runners. Multiple gate locations are advantageous for rapid and uniform mold filling and minimized potential air inclusions, but cooling of the casting material must be expected on the way from the branching point of the distributor unit to the gate locations. The latter can lead to a deterioration in the structural quality of the cast part and, in some cases, to casting defects.

[0006] To eliminate this problem, it has also become known to heat the distributor unit beyond the branch point and therefore essentially up to the gate position. However, in practice, it has been shown that in the case of heating the entire length of the distributor unit and / or the necessary manufacturing from different materials, the runners can disadvantageously deteriorate at the operating temperatures, which are usually several hundred degrees Celsius, so that the outlet of the distributor unit no longer strictly withstands the gate position, resulting in difficulties during casting, in particular in that the material cannot be poured reliably as desired.

[0007] This is addressed by the present invention, whose object is to specify an apparatus of the type named at the outset, which is capable of producing metal components at high quality and with high process reliability.

[0008] Furthermore, it is an object to specify a method of the type named at the outset, which allows for the production of metal components with low wear and high quality. Summary of the Invention

[0009] According to the invention, this object is achieved with a device of the type named at the beginning, when at least one of the outlet channels is connected to the mold in a sliding manner to allow relative movement between the outlet nozzle of the outlet channel and the mold.

[0010] The present invention is based on the concept of counteracting the thermal expansion associated with the heating of the distributor unit, particularly its outlet channels, not through modified process control but through structural modifications to the device. When at least one, particularly multiple, outlet channels are connected to the mold in a sliding manner, typically using slip joints, the mechanical stresses generated by the thermal expansion of the distributor unit, particularly acting on the outlet nozzle, can be reduced or eliminated. Therefore, mechanical loads, particularly deformation of the outlet channel, possibly even to the point of its destruction, and / or distortion of the outlet nozzle can be avoided. Furthermore, wear on the distributor unit can be reduced or the service life of the device, particularly the distributor unit, can be increased, and the injection of casting material into the cavity, primarily during repeated repetition of the component manufacturing process using the device, can be achieved with high and particularly consistent quality. As a result, high process reliability is possible for the injection of casting material into the cavity and the production of high-quality components. This is particularly true when multiple, preferably all, outlet nozzles are connected to the mold in a sliding manner, particularly using this type of slip joint. The above-mentioned effect can be achieved with particular efficiency if each of the outlet channels is connected to the mold in a sliding manner so that the respective relative movements between the outlet nozzle and the mold are possible independently of each other.

[0011] It has been shown that the above-mentioned effects can also be achieved specifically when a metallic material in a thixotropic state is used as the casting material and / or when the distributor unit or its inlet and / or outlet channels are embodied as a hot runner system, thereby enabling high ease of operation of the device and the production of near-net-shape components with particularly high precision.

[0012] For high process reliability and component quality, it is advantageous if the outlet channels are connected to or positioned on the mold in a sliding manner, so that the outlet nozzles of the outlet channels can be displaced relative to the mold transversely or at an angle, particularly perpendicular, to the injection direction of the outlet nozzle. This allows for efficient compensation of thermal expansion occurring in the distributor unit, particularly the outlet channel. Typically, at least one of the outlet channels is connected to the mold in a sliding manner, particularly by means of a slip joint, so that relative movement between the outlet nozzles of the outlet channel and the mold is possible to a limited extent in a direction transverse, particularly perpendicular, to the injection direction of the outlet nozzle, in order to allow for relative movement between the outlet nozzles caused by thermal expansion of the distributor unit.

[0013] When the distributor unit or outlet channel is at the casting temperature, it is advantageous if the outlet opening of the outlet nozzle of the outlet channel and the injection opening of the mold are aligned so as to be essentially flush with each other by sliding the outlet nozzle relative to the mold in order to inject the casting material through the outlet opening into the cavity. Because the outlet nozzle is aligned with the injection opening of the mold in this manner, high precision can be achieved when filling the cavity. Typically, at least one outlet nozzle is aligned with the injection opening of the mold, through which the casting material can be injected into the cavity of the mold when the distributor unit is at the casting temperature. This provides, through sliding the outlet nozzle relative to the mold, that the outlet opening of the outlet nozzle and the injection opening are aligned so as to be essentially flush or centered when the distributor unit or outlet channel is at the casting temperature. Typically, when the distributor unit or outlet channel is at a non-casting temperature, particularly at room temperature, the outlet opening of the outlet nozzle is not flush with or off-center from the injection opening, and when the distributor unit or outlet channel is at a casting temperature, it is provided that it is displaced by sliding to a flush or centered position when the casting material can be injected into the mold. As a result, the casting material can be injected into the cavity in a predefined manner using the outlet nozzle, particularly with precise angular alignment, thereby reducing or avoiding casting defects. It is understood that the non-casting temperature thereby typically refers to a temperature lower than the casting temperature, at which the casting material is not injected through the distributor unit or outlet channel or the distributor unit is not filled with flowable casting material.

[0014] A robust connection can be achieved if the outlet channel and the mold are connected to each other in a sliding manner in a form fit, and the relative movement between the outlet nozzle of the outlet channel and the mold is possible to a limited extent in a direction transverse to the injection direction of the outlet nozzle. A form fit is a connection through spatial embedding. It is advantageous if the form fit or form fit connection is realized in such a way that the relative movement between the outlet nozzle and the mold is possible to a limited extent in multiple directions, in particular in directions aligned perpendicular to each other or along an axis of this type. The direction or axis thereby typically lies in one plane, usually in a plane perpendicular to the injection direction of the respective nozzle. In this way, a sliding joint can be realized in a simple and flexible manner using this type of form fit between the outlet channel and the mold.

[0015] It is practical if the outlet channel has an outer diameter that varies along its longitudinal axis to create a form fit between the outlet channel and the mold. Therefore, a flexible, form-fit connection can be easily manufactured between the outlet channel and the mold. For example, the mold can be provided with a connecting element or receptacle that engages behind a region of the outlet channel or that engages a region of the outlet channel with a reduced outer diameter, thus creating a form fit.

[0016] For a flexible connection, it is advantageous if the outlet channel has a foam extending along the periphery of the outlet channel to create a form-fit between the outlet channel and the mold. Advantageously, the foam can be inserted into a receptacle in the mold with a form-fit and provided with the ability to move in a sliding manner. The connection is particularly robust if the foam extends along the periphery of the outlet channel in a ring shape. Therefore, loads acting on the foam, especially tensile loads in the axial direction of the outlet channel or its outlet nozzle, can be uniformly distributed around the periphery of the outlet channel. Alternatively, multiple foams can be arranged along the periphery of the outlet channel to achieve the same effect. It should be understood that, similarly, this type of foam can be arranged on the mold and the receptacle, for example, on the outlet channel, to achieve a connection with a corresponding effect. Generally, this type of connection, having any desired specific design, is sufficient, provided that the spatial embedding of the foam that allows sliding according to the present invention is performed.

[0017] A preferably flat contact surface is arranged on the end piece of the outlet channel having the outlet nozzle, and a slip joint is produced when the contact surface is placed in a sliding manner on a corresponding mounting surface of the mold to connect the outlet channel to the mold in a sliding manner. This allows for a low-tolerance implementation of the slip joint. It is advantageous if the outlet channel and the mold are connected in a manner that seals the casting material, or if a slip joint is realized in a manner that seals the casting material. This can be achieved in a particularly efficient manner using the above-mentioned mounting of the contact surface and the mounting surface on each other. In many cases, a compression or frictional connection exists between the contact surface and the mounting surface to achieve leak-tightness for the casting material, and the static friction coefficient of the compression or frictional connection is selected in a limited manner to allow sliding between the contact surface and the mounting surface when thermal expansion of the distributor unit occurs. Alternatively or additionally, a sealing element, particularly multiple sealing elements, can be arranged between the contact surface and the mounting surface to achieve leak-tightness for the casting material. The sealing element can be made of a metallic material, such as copper or a ceramic material. The sealing element is often embodied as a sealing ring. For robust sliding, it is advantageous if the outlet nozzle opening of the outlet nozzle is bounded or surrounded by a contact surface. This is particularly true in cross sections through the outlet nozzle. Therefore, directionally independent sliding is particularly easily achievable. For this purpose, it has proven effective if the outlet nozzle or the outlet nozzle opening opens onto the contact surface.

[0018] High practicality can be achieved when the end piece of the outlet channel is inserted, particularly removably, into the end bushing, which constitutes an enlargement of the outer diameter of the outlet channel in order to connect the outlet channel to the mold in a sliding manner, particularly by creating a form fit. A form fit can therefore be easily manufactured. It is practical when the end bushing forms a contact surface. The end bushing is typically embodied to at least partially, preferably completely, surround or grip the end piece of the outlet channel in the circumferential direction. It is even more advantageous when the end bushing grips, particularly the side of the end piece facing the mold, thereby forming a contact surface when the end bushing is connected to the mold. The end bushing can be embodied, for example, as a cup-shaped attachment fitted onto the outlet channel, the base of which has a passage corresponding to the outlet nozzle, through which the casting material can be guided using the outlet nozzle. The outlet nozzle is typically at least partially, particularly completely, inserted into, or fed through, the passage or opens into the passage. Preferably, thermal expansion of the outlet nozzle, particularly in the injection direction relative to the end bushing, is thus permitted. Advantageously, the end bushing can be connected to the outlet channel or end piece in a form-fit and / or force-fit and / or material-bonded manner, or can be embodied as part of the outlet channel or end piece. For easy maintenance, it is advantageous if the end bushing is detachably connected to the outlet channel or its end piece. In particular, the end bushing can therefore be easily maintained and / or replaced as a wear-prone part. Since the end bushing increases the outer diameter of the outlet channel or end piece, a robust form fit that allows the slip joint to slide can be realized in a simple manner. In particular, the above-mentioned compressive or frictional connection between the contact surface and the resting surface can be preferably adjustably realized in that the end piece or end bushing is pressed against the mold using a fastening element.For this purpose, a typically detachable form-fit and / or force-fit connection between the end bushing and the fixing element can be provided.

[0019] A durable design can be achieved when the mold comprises a receptacle embodied as a recess in the mold into which the end piece, and possibly the end bushing, is at least partially, particularly completely, inserted to create a form fit. Therefore, in particular, unwanted leakage of the casting material between the end piece and the outer mold surface can be effectively prevented or the potential risk thereof can be minimized. The respective injection openings of the mold, through which the casting material can be injected into the cavity using the respective outlet nozzles, are typically arranged in the base surface of the receptacle. It is advantageous if the resting surface, on which the contact surface rests in a sliding manner, is formed by a surface of the receptacle that defines the receptacle, e.g., the base surface or a wall surface. The end piece is thereby typically removably inserted into the receptacle with a form fit.

[0020] For high practicality, a locking device is present, which is useful when it prevents, in particular reversibly, the release of the sliding connection or form fit between the outlet channel and the mold. For this purpose, the locking device can advantageously comprise a locking element that engages behind the foam or end bushing to create a form fit, in particular releasably. For a highly reliable fixation, this has proven effective when the locking element surrounds the outer periphery of the outlet channel or its end piece to secure the foam or end bushing in place. For this purpose, it is practical when the locking element comprises a feed-through opening through which the outlet channel or its end piece is guided, the feed-through opening having an inner width or inner diameter smaller than the outer width or outer diameter of the outlet channel or end bushing, in order to connect them with a form fit so that they can slide. To remove the end piece or end bushing from the mold, a simple process can be achieved when the form fit can be reversed by moving, in particular sliding or pivoting, the locking element relative to the mold. It is usually sufficient if the connection between the locking element and the mold is realized using a threaded connection or an equally convenient releasable connection. It has proven effective if the receptacle can be at least partially locked using a locking device to fix, in particular releasably, the end piece or end bushing in place in the receptacle with a form fit or to surround it in the receptacle so that it can slide. In particular, the above-mentioned fixing element can be conveniently formed using the locking element.

[0021] It is advantageous if a cooling device is provided to cool the end bushing and / or mold, particularly the receptacle. Therefore, sliding of the slip joint, particularly between the contact surface and the resting surface, can be made possible independently of the operating or casting material temperature. This is advantageous for reproducibly ensuring precise positioning or alignment of the outlet nozzle relative to the cavity or injection opening. Therefore, leakage of casting material, particularly between the outlet channel and the mold, particularly along the contact surface, can be prevented by solidification of the leaking casting material. The cooling device can be formed using one or more cooling channels through which a cooling medium can flow. These channels are typically arranged in or inside the walls forming the end bushing, or the mold or receptacle. It is advantageous if the end bushing and the mold or receptacle can be cooled separately from each other, or if the end bushing or mold each has its own cooling device, e.g., cooling channels that can be controlled separately from each other. However, in many cases it is sufficient if the end bushing and mold are cooled by a shared cooling device or one or more shared cooling channels.

[0022] It is advantageous if there is at least one temperature control device, which can be used to temperature-control the outlet channel, particularly by heating or cooling it. Therefore, the casting material located in the outlet channel can typically be brought to the casting temperature after or before the execution of the pouring operation. This proves effective when the outlet channel is temperature-controlled so that the casting material located in the outlet channel is maintained in a flowable state for subsequent pouring into the mold. It is also advantageous if the casting material located in the outlet channel does not solidify or is maintained in a flowable state between two pouring operations, particularly for the entire duration. The thermal expansion and accompanying mechanical stress loads associated with heating the distributor unit or outlet channel over such an extended period of time can be advantageously compensated to a significant extent by a slip joint between the outlet channel and the mold. This is particularly true when a thixotropic metallic material or a metallic material in a thixotropic state is used as the casting material. The material is usually maintained in a thixotropic state between two pouring operations. The distributor unit or outlet channel can be conveniently embodied as a hot runner system, in which the casting material located in the distributor unit or outlet channel between two pouring operations or pouring cycles is held flowably. Typically, a plug is formed in the outlet nozzle after the pouring operation due to solidification of the casting material, and this plug conveniently seals the outlet nozzle. In this way, outflow or afterflow of the flowable casting material, especially the casting material held flowably by heating arranged downstream of the plug, is efficiently prevented. It is convenient for the temperature control device to be embodied as a heating device and / or a cooling device. The temperature control device can be formed with one or more temperature control channels through which a temperature control means, for example, a heating medium or a cooling medium, can flow to temperature control, especially heating or cooling, the outlet channel or outlet nozzle. Alternatively or additionally, the temperature control device can be formed with one or more electric resistance heaters.This proves particularly effective when, alternatively or cumulatively, the temperature control device is embodied using an electric induction heater to heat the casting material located in the outlet channel using electric induction. For precise temperature control, it is advantageous when multiple, especially separately controllable, temperature control devices as described above are arranged along the outlet channel. It is particularly advantageous when the temperature control of the outlet nozzle and one or more outlet channel segments of the outlet channel leading downstream toward the outlet nozzle can be controlled independently of each other. As a result, plug formation in the outlet nozzle and maintaining the flowable state of the additional or remaining casting material in the outlet channel can be precisely controlled independently of each other. This can be practically realized when the outlet nozzle and the outlet nozzle segments can be temperature-controlled using separate, especially different, temperature control devices as described above. This proves particularly effective when the outlet nozzle or the casting material located therein can be heated using at least one induction heater. As a result, the pouring operation and / or plug formation after the pouring operation can be controlled in a particularly precise manner. For this purpose, an electric induction heater, in particular a plurality of heaters of this type, can be practically arranged, preferably on the end piece or in the region of the outlet nozzle, so that it surrounds the channel run of the outlet nozzle in the circumferential direction. For flexible temperature control, it is advantageous if the outlet channels, in particular the outlet nozzle, can be temperature-controlled separately from one another. For this purpose, there can be a plurality of the above-mentioned temperature control devices, typically arranged in different outlet channels or outlet nozzles.

[0023] It is to be understood that the above features presented or described on the basis of or with reference to an outlet channel or its outlet nozzle apply analogously to other or further envisaged outlet channels or its outlet nozzles, or are instead expressly and preferentially provided.

[0024] Typically, at least one of the outlet channels is formed by a plurality of longitudinal segments that are connected to or in contact with one another, and whose longitudinal axes are angled relative to one another to redirect the casting material using the longitudinal segments. As a result, redirection of the casting material can be practically achieved using a distributor unit to distribute the casting material to the plurality of outlet channels. Typically, the longitudinal segments are embodied so that they are in direct contact with one another, but it is also possible for them to be indirectly in contact with one another, for example, via an intermediate element. It is advantageous if multiple, and often all, of the outlet channels are embodied in this manner. Here, it is beneficial if two adjacent longitudinal segments each have longitudinal axes that form an obtuse angle. Therefore, redirection of the casting material guided through the longitudinal segments can be kept small, avoiding pressure drops and pressure peaks in the casting material and force peaks in the longitudinal segments. It is particularly beneficial if all of the longitudinal segments are embodied in this manner.

[0025] To distribute the casting material, it is usually provided that the different outlet channels are at least partially aligned at an angle to one another. This type of design is usually particularly susceptible to mechanical stresses as a result of thermal expansion, which can lead to particularly significant relative movements between the outlet channels and the outlet nozzles, which can be significantly minimized by the slip joint between the outlet channels and the mold, as presented above. It is advantageous if several, in particular all, of the outlet channels are aligned symmetrically, in particular rotationally symmetrically or mirror-symmetrically with respect to a mirror axis. Therefore, the load or relative movements between the outlet channels can be reduced, so that, in combination with the provided slip joint, pouring operations that can be performed with particular precision and with almost no mechanical loads can be realized.

[0026] The outlet channels are typically formed using pipes that are usually connected, thereby directing the casting material to one or more shared inlet channels of the distributor unit. Conveniently, the inlet channels can also be formed using pipes. For a particularly robust design, it can be advantageous if the distributor unit is formed with a distributor body that includes at least one inlet channel section and multiple outlet channel sections connected thereto for directing the casting material, thereby allowing the casting material directed to the inlet channel section to be further directed via the outlet channel section. A further outlet channel piece, typically formed using pipes, is then connected to the outlet channel section to further direct the casting material directed via the outlet channel section to the mold, particularly in the manner described above. The distributor body can also include multiple inlet channel sections connected to the outlet channel section for directing the casting material. Since the branching of the casting material into the multiple outlet channels occurs within the distributor body, mechanical stresses and thermal expansion can be distributed in a particularly uniform manner. Conveniently, the distributor body can include one or more of the above-mentioned temperature control devices.

[0027] Typically, it is provided that the different outlet channels, in particular when they are formed using pipes, are spaced apart from one another in a direction transverse to the longitudinal axis of the pipe, so that a sliding movement of the outlet channels or outlet nozzles relative to the mold can be carried out in particular with little mutual interference.

[0028] Typically, a slip joint is provided that allows movement of the outlet nozzle relative to the mold in a direction transverse to, and especially perpendicular to, the pouring direction of the outlet nozzle by a few millimeters, typically at least 2 mm, usually at least 3 mm, often at least 4 mm, and preferably at least 5 mm. It is understood that, depending on the requirements, this type of movement can also be at least 8 mm, at least 10 mm, or at least 15 mm. Typically, a relative movement of between 2 mm and 15 mm, especially between 3 mm and 10 mm, preferably around 5 mm, is thereby permitted.

[0029] Another object of the present invention is achieved by a method for producing at least one metal component of the type named at the beginning, when at least one of the outlet channels is connected to the mold in a sliding manner to allow relative movement between the outlet nozzle of the outlet channel and the mold, particularly in a direction transverse to the injection direction of the outlet nozzle. Typically, at least one of the outlet channels is connected to the mold in a sliding manner by a slip joint, thereby allowing relative movement between the outlet nozzle of the outlet channel and the mold to a limited extent in a direction transverse to the injection direction of the outlet nozzle. As a result, relative movement between the outlet nozzles caused by thermal expansion of the distributor unit can be allowed. As explained above, components can be produced in this manner with high process reliability and high component quality. In particular, wear and load on the distributor unit can be reduced, and the injection of casting material into the mold cavity can be performed with high and consistent quality. Therefore, several or all of the outlet channels are advantageously connected to the mold in this type of sliding manner.

[0030] It is to be understood that the method according to the invention can be embodied within the scope of the device according to the invention in a manner corresponding to or similar to the features, advantages and effects described, in particular those described above, and the same applies to the device according to the invention in particular with respect to the described method according to the invention, as described below.

[0031] To produce one or more components, outlet channels can be used to guide the casting material into one or more cavities of a mold. The outlet channels are typically implemented as runners. This proves particularly beneficial when multiple outlet channels, especially when all outlet channels guide the casting material into a shared cavity, are used. Therefore, the cavities can be filled simultaneously via multiple outlet nozzles or injection openings, thereby achieving efficient filling of the cavities with few casting defects. The cavities are thereby typically filled simultaneously using multiple outlet nozzles spaced apart from one another. When the outlet nozzles are connected to the mold in a sliding manner, mechanical stresses acting on the outlet nozzles can be compensated for by sliding displacement of the outlet nozzles relative to the mold in a direction transverse or at an angle, especially perpendicular, to the injection direction.

[0032] Preferably, the outlet channel is heated after the injection of the casting material to prevent total or complete solidification of the casting material located in the outlet channel or to maintain the casting material located in the outlet channel in a flowable, particularly fluid, state. Typically, a plug is formed using the solidified casting material, while the casting material located downstream of the plug is simply maintained in a flowable state in the outlet channel by heating to prevent total solidification of the casting material located in the outlet channel. This can be achieved using a temperature control device, particularly a heating device, to heat the casting material, as described above. In many cases, the casting material located in the outlet nozzle is solidified or allowed to solidify to form a plug that prevents leakage of the flowable casting material located downstream of the plug in the outlet channel. The flowable casting material located in front of the plug in the outlet channel is thereby heated to prevent its solidification, typically until the next injection operation or until the creation of the next component. The extended temperature load associated with the heated casting material and the accompanying thermal expansion of the distributor unit or outlet channel can be largely compensated for by a sliding connection between at least one outlet channel and the mold.

[0033] Particularly high casting accuracy can be achieved when a sliding movement of the outlet nozzle relative to the mold is performed, whereby, when the outlet channel is at the casting temperature, the outlet opening of the outlet nozzle of the outlet channel and the injection opening of the mold are aligned essentially flush with each other in order to inject the casting material through the injection opening into the cavity through the outlet opening. The sliding movement is typically caused by thermal expansion of the distributor unit, especially the outlet channel, or during heating of the distributor unit or the outlet channel. Here, it is advantageous if at least one outlet nozzle is aligned with the injection opening of the mold, through which the casting material is injected into the cavity using the outlet nozzle when the distributor unit or the outlet channel is at the casting temperature, whereby the sliding movement of the outlet nozzle relative to the mold is performed so that a flush or centered position between the outlet opening of the outlet nozzle and the injection opening is assumed at the casting temperature. Typically, at least one outlet nozzle is aligned with the mold's injection opening so that the outlet opening of the outlet nozzle is off-center from the injection opening at non-casting temperatures, especially room temperature, and is displaced or displaced by sliding to a flush, centered, or concentric position at the casting temperature. At the casting temperature, the casting material can be injected into the mold, and the outlet channel is heated to the casting temperature. Depending on the casting material, the casting temperature is usually several hundred degrees Celsius, often around 600 degrees Celsius, for example, for casting materials formed using magnesium alloys. The relative displacement between the outlet channel and the mold associated with thermal expansion is usually several mm. The outlet nozzle is adjusted to be displaced to a corresponding extent, so that optimal flush or centered alignment can be achieved at the casting temperature.

[0034] Additional features, benefits, and advantages will become apparent from the exemplary embodiments described below. In the drawings referenced thereby: [Brief explanation of the drawings]

[0035] [Figure 1] 1 is a schematic diagram of an apparatus for manufacturing metal components using the thixomolding method. [Figure 2] FIG. 2 is a schematic spatial view of the distributor unit. [Figure 3] 1 is a schematic view of a distributor unit in a longitudinal section through the distributor unit; FIG. [Figure 4] FIG. 10 is a schematic diagram of an end piece of an outlet channel with an end bushing. [Figure 5] 5 is a schematic diagram of a mold having a receptacle corresponding to the end piece from FIG. 4 into which the end piece can be inserted to form a slip joint. [Figure 6] 6 is a schematic view of the end piece from FIG. 4 in an inserted state in the receptacle from FIG. 5. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0036] 1 shows a schematic diagram of a typical apparatus 1 for producing metal components 2 by injecting a flowable, in particular thixotropic, metal casting material into the cavities 4 of a multi-component mold 3. This type of apparatus 1 typically comprises a filling chamber, also called a barrel, a conveying unit, often embodied as a screw conveyor, a distributor arranged downstream after the filling chamber (through which the casting material is conveyed under pressure from a conveying device 5 formed together with the filling chamber and the conveying unit to the mold 3 for injecting the casting material into the cavities 4 of the mold 3), and the mold 3 arranged behind the distributor unit 6. The distributor unit 6 comprises at least one inlet channel 7 connected to the conveying device and several outlet channels 8 connected to the mold 3 for filling the cavities 4 of the mold 3 with the casting material in a time-parallel manner via the outlet channels 8. For this purpose, each outlet channel 8 comprises one outlet nozzle 9 by means of which the casting material can be injected into the cavities 4 through one injection opening 10 in the mold 3, each corresponding to the respective outlet nozzle 9. A distributor unit of this type is shown, for example, diagrammatically in FIG. 2 or FIG.

[0037] As can be seen in FIG. 1 , a multi-component mold 3 is typically formed using a stationary first plate and a movable second plate relative to the first plate. The surfaces of the first and / or second plates have the negative shape of the component 2 to be produced. By placing the first and second plates together, the mold is closed and a cavity 4 corresponding to the component 2 is formed. Outlet nozzles 9 typically connect to the first plate, allowing the casting material to be injected into the cavity 4 through the outlet nozzle openings of the respective outlet nozzles 9. In the case of processing thixotropic casting materials, the filling chamber typically includes a heater, which is used to bring the casting material into a thixotropic state, typically with simultaneous shearing of the casting material using a screw conveyor. Subsequent injection of material into the cavity 4 of the mold 3 through the outlet nozzles 9 typically occurs via a distributor unit 6 or a forward axial movement of the screw conveyor in the direction of the outlet nozzles 9.

[0038] 1 shows a state of the method after solidification of the component 2 in the mold 3. A plug of solidified casting material is thereby usually formed at the outlet nozzle 9 in order to prevent the flowable casting material located downstream in front of the plug from leaking out of the outlet nozzle 9, particularly in the processing of casting material in a thixotropic state. In FIG. 1, the mold 3 is open and the produced component 2 is removed from the mold 3 using a robot arm. In the next production cycle, during the injection of casting material into the mold for producing the next component 2, each plug of this type is typically pressed or ejected into the cavity 4 as well.

[0039] 2 and 3 show schematic diagrams of a distributor unit 6 that can be used, for example, in the apparatus 1 from FIG. 1 . The distributor unit 6 has an inlet channel 7 and two outlet channels 8 for supplying the casting material supplied via the inlet channel 7 to the mold 3 via the outlet channel 8. Each of the outlet channels 8 includes an outlet nozzle 9 through which the casting material can be injected into the cavity 4. The outlet channels 8 are formed using pipes connected to the inlet channel 7 to guide the casting material. The different outlet channels 8 are typically spaced apart from each other in a direction transverse to the longitudinal axis of the outlet channels 8 to minimize mutual interference, for example, due to mechanical forces and / or thermal expansion. To achieve high robustness, the distributor unit 6 can be formed with a distributor body 11 including an inlet channel section and two outlet channel sections for distributing the casting material via the inlet channel section to the outlet channel section. The inlet channel section and the outlet channel section are typically connected to each other at a shared joint to guide the casting material. The outlet channel portion formed by means of a pipe typically connects to an outlet channel section for further directing the casting material into the mould 3. Conveniently, the distributor body 11 may include one or more heating devices 24.

[0040] In order to avoid mechanical stresses leading to deformation or buckling of the outlet channels 8, the outlet channels 8 are connected to the mould 3 in a sliding manner by means of a slip joint, so as to allow relative movement between the respective outlet nozzle 9 and the mould 3 in a direction transverse to the longitudinal axis of the outlet channel 8 or the pouring direction of the outlet nozzle 9. In this way, mechanical stresses caused by thermal expansion can be relieved in the form of relative movement between the outlet nozzle 9 or the outlet channel 8.

[0041] FIG. 4 shows an end piece 13 of the outlet channel 8, which includes the outlet nozzle 9. The outlet channel 8 from FIGS. 1 to 3 can be conveniently embodied in this manner. The end piece 13 includes a temperature control device, preferably embodied as an induction heater 14, for temperature control, in particular heating, of the casting material located at the outlet nozzle 9. The end piece 13 of the outlet channel 8 is inserted into an end bushing 15, which surrounds the periphery of the outlet channel 8 with a form-fitting first end bushing section 16 and grips the side of the outlet channel 8 facing the mold 3 with a second end bushing section 17. The first end bushing section 16 enlarges the outer diameter of the end piece 13 to connect the end piece 13 to the mold 3 with a form-fitting. The second end bushing section 17 forms a contact surface 18 for slidingly setting the corresponding bearing surface 19 on said surface. The end bushing 15 can advantageously be embodied in the shape of a cup, the cup bottom of which provides a passageway through which the outlet nozzle 9 opens or through which the outlet nozzle 9 is at least partially guided. As can be seen in Figure 4, it is advantageous if the end bushing 15 is cooled by means of a cooling device, for example by means of cooling channels 12.

[0042] Figure 5 shows a schematic view of a segment of a mold 3, for example the mold 3 according to Figure 1. The mold 3 has a receptacle 20 corresponding to the end piece 13 from Figure 4, into which the end piece 13 or an end bushing 15 can be inserted to form a slip joint. The receptacle 20 is typically embodied as a recess in the mold 3, and an injection opening 10 of the mold 3 is arranged in its base surface, through which the casting material can be injected into the cavity 4 using an outlet nozzle 9. The mold 3, or its receptacle 20, includes a locking device 21 by means of which the receptacle 20 can be locked so that the end bushing 15 inserted therein is enclosed therein with a form fit, thereby allowing sliding movement of the end bushing 15 in the receptacle 20 transversely, in particular perpendicularly, to the injection direction of the outlet nozzle 9 of the end piece 13. The locking device 21 can conveniently be releasably connected to a part of the mold 3 by means of a threaded connection. Furthermore, a plug receptacle 22 is visible in FIG. 5, which is embodied as a part facing the injection opening 10 of the cavity 4 for receiving a plug ejected from the outlet nozzle 9 during injection of the casting material into the mold 3. Typically, the mold 3 includes an ejector unit 23 by means of which the component 2 solidified in the cavity 4 can be pushed out of the cavity 4 by displacement of the ejector unit 23. The mold 3 typically includes one or more cooling devices, typically in the form of cooling channels 12, for cooling the mold 3. Preferably, the mold 3 and the end bushing 15 include cooling channels 12 that can be controlled independently of each other, or each includes its own cooling device.

[0043] Figure 6 shows a schematic diagram of the end piece 13 of the outlet channel 8 from Figure 4, which is inserted with a form fit into the receptacle 20 from Figure 5, thereby allowing sliding movement of the end piece 13 in one or more directions of movement G transverse to the injection direction of the outlet nozzle 9 of the end piece 13. The outlet opening of the outlet nozzle 9 is thereby aligned so as to be centered with the injection opening 10 of the mold 3 for injecting the casting material into the cavity 4 through the outlet nozzle 9.

[0044] Preferably, the mould 3 comprises a number of receptacles 20 of this type for inserting, with a form fit, each end piece 13 or end bushing 15 of one of the outlet channels 8, so that each end piece 13 can be moved in sliding manner in a direction transverse to the injection direction of the respective outlet nozzle 9. Preferably, each of the outlet channels 8 is connected to the mould 3 in this way in sliding manner.

[0045] At least one of the outlet channels 8, typically all of the outlet channels 3, is connected to the mold 3 in a sliding manner, which allows the respective outlet nozzle 9 to be moved relative to the mold 3 in a direction transverse to the injection direction of the nozzle, so that thermal expansion of the distributor unit 6 or of the outlet channels 8 that occurs during operation can be compensated for. Disturbances in the injection operation can thus be minimized or prevented, which allows the metal component 2 to be produced with high process reliability and high quality.

Claims

1. 1. An apparatus for producing at least one metal component by injecting a flowable metallic casting material into at least one cavity of a multi-part mold, the apparatus comprising: a conveyor device for the flowable metallic material; a distributor unit; and the multi-part mold, arranged in sequentially downstream order; wherein the distributor unit has an inlet channel connected to the conveyor device and a plurality of outlet channels, each having an outlet nozzle, whereby the metallic casting material supplied under pressure through the inlet channel can be injected through the outlet nozzle into the at least one cavity of the multi-part mold so as to simultaneously fill the at least one cavity with the metallic casting material through the outlet nozzle; and at least one outlet channel of the plurality of outlet channels is connected to the multi-part mold in a sliding manner to enable relative movement between the outlet nozzle of the outlet channel and the multi-part mold in a direction transverse to the injection direction of the outlet nozzle.

2. 2. The apparatus of claim 1, wherein the outlet channel is connected to the multi-component mold in a sliding manner, thereby allowing the outlet nozzle of the outlet channel to be displaced transversely to the injection direction of the outlet nozzle relative to the multi-component mold.

3. 3. The apparatus of claim 1, wherein when the outlet channel is at a casting temperature, the outlet opening of the outlet nozzle of the outlet channel and the injection opening of the multi-part mold are aligned coaxially with each other by sliding movement of the outlet nozzle relative to the multi-part mold for injecting the metallic casting material through the injection opening and into the cavity through the outlet opening.

4. 4. The apparatus according to claim 1, wherein the outlet channel and the multi-component mold are connected to each other in a sliding manner in a form-fit, allowing relative movement between the outlet nozzle of the outlet channel and the multi-component mold within a predetermined range in a direction transverse to the pouring direction of the outlet nozzle.

5. The apparatus of claim 4 , wherein the outlet channel has an outer diameter that varies along its longitudinal axis to create the form fit between the outlet channel and the multi-part mold.

6. 6. The apparatus of claim 4 or 5, wherein the outlet channel has a form extending in a ring shape around the periphery of the outlet channel to create the form fit between the outlet channel and the multi-part mold.

7. 7. The apparatus according to claim 1, wherein an end piece that forms the end of the outlet channel and holds the outlet nozzle is inserted into an end bushing, the end bushing being a cup-shaped attachment that is fitted onto the outer periphery of the outlet channel and expands the outer diameter of the outlet channel in order to connect the outlet channel to the multi-component mold in a sliding manner.

8. 8. The apparatus of claim 7, wherein a contact surface is disposed on the end piece of the outlet channel having the outlet nozzle, and the contact surface is slidably mounted on a mounting surface of the multi-component mold corresponding to the contact surface to connect the outlet channel to the multi-component mold in a sliding manner.

9. 9. The apparatus according to claim 7 or 8, wherein the multi-part mold has a receptacle embodied as a recess in the multi-part mold, into which the end piece is inserted for sliding connection of the outlet channel to the multi-part mold.

10. The apparatus of any one of claims 1 to 9, wherein a locking device is present, said locking device preventing release of the sliding connection between said outlet channel and said multi-part mould.

11. The device according to any one of claims 1 to 10, wherein at least one temperature control device is present, said at least one temperature control device being able to control the temperature of said outlet channel.

12. 12. The device of claim 1, wherein at least one of the outlet channels is formed with a plurality of abutting longitudinal segments, the longitudinal axes of the longitudinal segments being at an angle to one another.

13. A method for making at least one metal component using an apparatus as described in any one of claims 1 to 12, wherein a flowable metal casting material is guided under pressure from a conveyor device through a distributor unit to a multi-component mold to make the metal component, the metal casting material is guided through at least one inlet channel of the distributor unit to a plurality of outlet channels of the distributor unit, and is injected into at least one cavity of the multi-component mold through the outlet nozzles of the outlet channels to simultaneously fill the at least one cavity with the metal casting material through the outlet nozzles, and at least one of the outlet channels is connected to the multi-component mold in a sliding manner to allow relative movement between the outlet nozzle of the outlet channel and the multi-component mold in a direction transverse to the injection direction of the outlet nozzle.

14. 14. The method of claim 13, wherein the outlet channel is heated subsequent to injection of the metallic casting material to prevent total solidification of the metallic casting material located in the outlet channel.

15. 15. The method according to claim 13 or 14, wherein a sliding movement of the outlet nozzle relative to the multi-component mold is performed, whereby, when the outlet channel is at a casting temperature, the outlet opening of the outlet nozzle of the outlet channel and the injection opening of the multi-component mold are aligned coaxially with each other for injecting the metallic casting material through the injection opening into the cavity through the outlet opening.

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