Method for producing a turbocharger assembly, turbocharger assembly and turbocharger

Abstract

Method for the additive manufacturing of a structure (3) in the form of a housing structure of a compressor housing of a turbocharger assembly (1) with increased containment safety, characterized by the following steps: - providing an arrangement (7) with a spray device (45) which is connected to a storage container (47) supplying the raw material, - spraying the powdered metallic base material (5) by means of the spraying device (45) and subsequent laser processing, whereby the structure (3) is manufactured layer by layer additively, - creating a structural cavity (35) with a cavity wall (37) with sufficient wall dimensions, - Suction of remaining base material (5) from the partially completed structural cavity (35), - introducing an insert element (43) into the cleared partial structure cavity, - Encapsulation of the insert element (43) with the completion of the remaining structural cavity (35), wherein the encapsulation is effected by a cavity wall (37) which completely encloses the structural cavity (35) and is completely additively manufactured.

Description

The present invention relates to a method for manufacturing a turbocharger assembly according to the preamble of claim 1.In the prior art, it is known from the publication EP 1 884 627 A1 to fill a cavity of a turbocharger with bulk material in order to increase containment safety with respect to a burst case and to damp oscillations at the turbocharger.From WO 2017 / 158 837 A1 a rotary machine is known, which is equipped with: a rotating body rotating about a central axis; and a housing accommodating at least a part of the rotating body. The housing is provided with: a main portion formed of a metallic material; and a high porosity portion formed of the same material as the main portion and having a higher porosity than the main portion.Proceeding from this, the object of the present invention is to specify a method for producing a turbocharger assembly which simplifies the production of a turbocharger, in particular of the aforementioned type, and helps to increase the structural strength thereof.This object is achieved by a method having the features of claim 1.Advantageous refinements and embodiments are specified in the further claims.According to the invention, a method for producing a turbocharger assembly, in particular for a turbocharger, preferably for an exhaust gas turbocharger, is proposed. A turbocharger formed with the turbocharger assembly is preferably provided for an internal combustion engine, that is, for causing supercharging thereon. Such a turbocharger may also be provided for register charging, for example as a basic supercharger or shift supercharger. Within the scope of the present invention, the turbocharger assembly can be, for example and preferably, an assembly of the compressor side (for example of a compressor housing), for example also an assembly of a filter muffler of the turbocharger or optionally also a structure of the turbine side of the turbocharger to be formed with the turbocharger assembly.According to the invention, it is provided that a structure of the turbocharger is additively manufactured, that is to say is manufactured by means of an additive manufacturing method, using the method. In general, in the context of the present invention, the terminology structure can be understood here to mean a structure or structure which consists of parts or components which mutually depend on one another or a self-structured whole (such as, for example, a housing structure, e.g. a compressor housing). In the present case, the additively manufactured structure is in particular a rigid, preferably metallic structure.The additive manufacturing method used within the scope of the method (which methods are therefore also referred to as generative manufacturing methods) is furthermore preferably one in which the manufacturing takes place starting from a bulk material-like or powdery base material or material.Particularly preferably, the additive manufacturing method is a layer construction method, further preferably, for example, a manufacturing method commonly referred to as "selective laser melting (SLM=selective laser melting)". In the SLM method known per se, homogeneous structures can be produced in an advantageously simple manner, in particular layer by layer (in this case the base material is melted layer by layer forming structure by means of laser), by means of structure design data, in particular CAD data, the base material, for example metal powder, and laser action, for example by means of 3-D lasers). This layer construction method can furthermore advantageously be used with a large number of different metals.In the method according to the invention, during or during this additive manufacturing of the structure (of the turbocharger assembly): a) a structure cavity (i.e. in particular a cavity of the structure) is created with a cavity wall; b) the structure cavity is furthermore at least partially filled with a filling material; and c) the filling material in the structure cavity is encapsulated by the created cavity wall (in particular by the additive manufacturing and furthermore in particular directly by the wall of the structure cavity). In particular, because the method can thus provide a completely homogeneously enclosed (and also filled) cavity, which is completely surrounded and in this case also completely enclosed, the rigidity of the structure achieved, and therefore of the turbocharger assembly, can advantageously be high.In the method, a structure cavity or a hollow mold is consequently formed (a)) in the structure, in particular by creating the cavity wall by means of additive manufacturing. The structural cavity or its wall is preferably formed by a layer structure as discussed above, within the scope of which the structural cavity is formed in particular successively.On the other hand, the structural cavity (insofar in particular within the cavity wall defining the cavity) is also filled (b)), in particular preferably completely. Provided as product for filling or filling material is a piece product, for example an insert element-like filling material in the form of an insert element, which can be handled in one piece, for example, and which is encapsulated within the scope of additive manufacturing. In this case, especially with the possibility of being able to base CAD data, for example, in the context of the additive method, the advantages result according to the method that the structural cavity or its cavity wall can be formed in a contour-adjusted manner to the piece-shaped filling material, for example, can be adapted to the filling material.With an insert element-like filling material, for example, the introduction of bulk material-like, e.g. granular, granulate-like or pellet-like, or powdery material into the structural cavity can furthermore be provided, e.g. in such a way that it is accommodated in a container-which overall forms the filling material-(i.e. the container together with material accommodated therein form the insert element).It is generally also conceivable that the filling material for filling the structural cavity comprises a combination of both material in pieces and material in bulk form and / or powder form.Within the scope of encapsulation c), the structure cavity-in this respect preferably with its completion within the scope of additive manufacturing of the structure-can be closed or sealed in particular completely, i.e. in particular by complete encapsulation, furthermore by an encapsulation which is manufactured completely additively. The encapsulation can preferably be effected by a final layer structure (of the cavity wall) preferably sealing the structure cavity in the context of the additive manufacturing method. Within the scope of the proposed method, steps a) to c) can be carried out-in the course of the additive manufacturing of the structure-in particular preferably in a single continuous operation of additive manufacturing, in particular without interruption of the same.Within the scope of the present invention, a turbocharger assembly is also proposed which is produced by a method as discussed above. A turbocharger, in particular an exhaust gas turbocharger, which has such a turbocharger assembly is likewise proposed. In such a turbocharger, the structural cavity can be in particular a structural cavity on the compressor side or on the compressor side of the turbocharger, for example also assigned to a filter muffler.An internal combustion engine, in particular of the reciprocating piston type, is also proposed which has at least one turbocharger as discussed above. Such an internal combustion engine can be designed as a self-igniter and / or a spark igniter, preferably e.g. as a diesel engine, in particular as a large engine. For example, the internal combustion engine can be provided for a motor vehicle such as, for example, a ship, a rail vehicle such as a locomotive, a commercial or special vehicle or, for example, for a stationary device, for example, for a combined heat and power plant, an (emergency) power unit, and also for industrial applications, for example, offshore.Further features and advantages of the invention are evident from the following description of exemplary embodiments of the invention, on the basis of the figures of the drawings, which show details essential to the invention, and from the claims. The individual features can each be realized individually or severally in different combinations in a variant of the invention.Preferred embodiments of the invention are explained in more detail below with reference to the attached drawings. The following are shown: FIG. 1 is an exemplary and schematic fragmentary view illustrating in more detail the technological background for the method according to the invention by way of example. FIG. 2 is an exemplary and schematic cross-sectional broken-away view of a turbocharger assembly obtainable with a method according to FIG. 1, wherein the structure is illustrated in an assembled state with a further component of a turbocharger. FIG. 3 shows, by way of example and schematically, a view illustrating the method according to the invention in more detail by way of example according to a possible configuration.In the following description and the drawings, the same reference numerals correspond to elements having the same or comparable function.FIG. 1 shows a view which illustrates in more detail the method for producing a turbocharger assembly 1 according to a first possible configuration.The turbocharger assembly 1 which is produced by the method has a structure 3 which is additively manufactured within the scope of the proposed method, in the present case within the scope of a laser melting method (SLM method). In the embodiment of the method illustrated by way of example in FIG. 1, a structure 3 in the form of a housing structure of a compressor housing of the turbocharger assembly 1 is, for example, additively manufactured.In the context of the laser melting method, a powdered material or base material 5 is melted layer by layer, i.e. layer by layer, and thus forms the structure 3 to be produced. the base material 5 is in particular metallic, in the present case e.g. a metal powder, i.e. generally a powder- or bulk-material-like base material 5.For carrying out the method, in the embodiment according to FIG. 1, an arrangement 7 is provided which comprises a supply and application device 9 for the base material 5, furthermore a work station 11 with a work platform 13, which can be lowered in particular, and furthermore a laser device 15 which is configured for generating and controlling the beam of a laser beam 17. The laser device 15 comprises, for example, a 3D laser.Within the scope of the arrangement 7, the base material supply and application device 9 comprises a piston 19 on which a base material supply 21 is stored, insofar as a supply piston 19, furthermore an application element 23, in the present case for example a roller element (alternatively for example a spatula), with which base material 5 can be transferred from the base material supply 21 by (laterally) displacement towards the work station 11 and there a respective base material layer or working plane 25 can be applied forming above the working platform 13. In this respect, a respective layer forming the working plane 25 is in particular a respective layer deposited last.The work station 11 comprises a lowerable piston 27, insofar as a working piston 27 is guided in a cylinder 29. In this case, the wall of the cylinder 29 (open at the top) closes on the working end side, Bz. 31, flush with that of the cylinder 33 (likewise open at the top) of the supply piston 19 or flush therewith. In the context of additive manufacturing, the structure 3 of the turbocharger assembly 1 is formed at the work station 11, that is to say by means of that base material 5 which is conveyed layer by layer to the work station 11 on the part of the supply piston 19 and of the application element 23 and forms a respective working plane 25, that is to say is deposited over the working platform 13.The laser device 15 is now configured to melt the base material 5 of the respective layer on the working plane 25 according to the predetermined structural data on the basis of construction or architecture data imaging the structure 3 via beam control (of the laser beam 17), insofar as the structure 3 is formed layer by layer by means of the base material 5 melted following the structure. For control purposes, CAD data, for example, can be used in an advantageously simple manner.With the arrangement 7 proposed, additive manufacturing can generally take place as discussed below.Starting from a starting position of both the base material supply and application device 9 and the work station 11, in which starting position the level of the working platform 13 comes to lie slightly, in particular by a predetermined height, which furthermore corresponds in particular to an intended (application) layer thickness of the base material 5, below the working end-side end 31 of the cylinder wall 33 and the level of the supply 21 at the same level in this case, the supply 21 is raised via the supply piston 19. Thus, base material 5 situated above cylinder end 31 can now be displaced (laterally) by application element 23 toward working platform 13, depositing a base material layer, in particular planar, which on the one hand forms working plane 25 for the intended introduction of laser energy and furthermore also has the intended layer thickness for melting base material 5.After the layer application is completed, the application element 23 can be moved back above the working platform 13 to the storage and application device 9.For the formation of further layers, analogously to this, the working piston 27 is again lowered by the height of a layer thickness, and the storage piston 19 is raised again as required for the transfer of the base material 5 of the new layer. The application element 23 can then deposit the new layer of the base material 5 over the working platform 13, that is to say after laser processing of the previous layer has been carried out, wherein the new layer then again forms the working plane 25.As soon as a respective layer has been deposited at the work station 11, i.e. forming the working plane 25, the layer or the base material 5 therein is melted via the laser device 15 according to the predetermined structure data, wherein the melted base material 5 is fused with the structure-shaped melted base material 5 of the previous layer to form the predetermined structure 3.In the context of the additive method, the layer formation and fusion is preferably carried out until the desired structure 3 is achieved or completed. A homogeneously constructed structure 3 can be obtained as can be seen here.Within the scope of the proposed method according to the invention, in the course of in particular such additive manufacturing of the structure 3, a hollow mold or a structure cavity 35 of the structure 3 with a cavity wall 37 is created (a)). The structural cavity 35 is in particular one which is likewise predefined by the architecture of the turbocharger assembly 1 and which is therefore preferably also predefined by structural data within the scope of the method for controlling the laser beam 17 of the laser device 15.Furthermore, according to the invention, (b)) the structural cavity 35 is also at least partially filled with a filling material 39, in the course of additive manufacturing, in particular during the duration of additive manufacturing and furthermore in particular associated with additive manufacturing.In the embodiment of the method according to FIG. 1, the structural cavity 35 is in particular advantageously already filled simultaneously with its formation or creation, in the present case in particular by leaving the material or the base material 5 of those layers, which is located within the structural cavity 35 to be created, in unmelted powder form therein, so that the structural cavity 35 is filled layer by layer until it is completed, that is to say with the base material 5 of the additive manufacturing method. In this case, the structural cavity 35 is preferably still completely filled. Furthermore, it is provided according to the invention that (c)) the filling material 39 is also encapsulated by the created cavity wall 37 of the structural cavity 35, cf. in particular FIG. 2, i.e. in particular by closing or sealing the structural cavity 35 (in the course of the additive manufacturing of the structure 3), so that the structural cavity 35 completely encloses the filling material 39 with its completion.Consequently, a turbocharger assembly 1 can be obtained with which the filling material 39 in the structural cavity 35 is surrounded on all sides by a homogeneous, in this respect high-strength and unbroked wall 37, so that the structural rigidity is advantageously increased in addition to containment safety, and therefore burst protection, compared to previously known solutions.It is evident that, with the proposed method, in a single, continuous working step, in which the (layer-by-layer) formation of the structure 3 or of the structure cavity 35 takes place within the scope of additive manufacturing, the filling of the structure cavity 35 can also take place simultaneously, and furthermore also its closure, in particular within the scope of the completion of the structure cavity 35.FIG. 2 now shows, in a broken-off sectional view, the turbocharger assembly 1 obtained with the method, in which the step-material-like powder or the base material 5 is encapsulated in the structural cavity 35 in a manner visible completely and homogeneously enclosed. The obtained turbocharger assembly 1 may then be assembled with one or more further turbocharger assemblies 41.FIG. 3 now illustrates, for the most exemplary purpose, an embodiment of the method according to the invention in which, in contrast to the technological background discussed above, an insert element 43 for filling the structural cavity 35 is additively manufactured and encapsulated by melting.For example, it can be provided here to deposit layer-forming base material 5 on the working platform 13 or the work station 11 via a supply and storage device 9, which, in contrast to the configuration of the arrangement 7 according to FIG. 1, has for this purpose a spraying device 45 which is connected to a base-material-supplying storage container 47, in addition to which the supply and storage device 9 provides, for example, neither a storage piston 19 nor a cylinder 33 nor an application element 23. In this embodiment of the arrangement 7, the working piston 27 or the working platform 13 can be mounted in a rotatable manner, for example, so that a respective base material application forming the working plane 25 is made possible within the scope of a rotation of the working piston 27.To create the turbocharger assembly 1 with the arrangement 7 according to FIG. 3, it can now be provided to form the structure 3 layer by layer in additive manufacture, i.e. by spray application of the base material 5 by means of the spray device 45 and subsequent laser processing until the structural cavity 35 created as a result has sufficient wall dimensions to fix the at least one insert element 43 to be introduced therein in a position-spread manner independently (this is appropriate, for example, if the insert element 43 is adapted to the contour of the structural cavity 35). Any base material 5 remaining in the partially finished structural cavity 35 up to then can be suctioned off, for example. In this respect, the arrangement 7 can have a suction device for this purpose (not shown). The insert element 43 can then be introduced into the cleared partial structure cavity and, during the further additive manufacturing, simultaneously with the completion of the remaining structure cavity 35 and its complete encapsulation with the melted base material 5, can be converted.Alternatively or additionally, the insert element 43 can also be held separately, for example, over at least a duration of the method.The insert element 43 provided as the filling material 5 can be, for example, a bulk material container which contains, for example, granules, powder, pellets or a granular substance or a combination of such bulk material-like substances.LIST OF REFERENCE CHARACTERS1 Turbocharger assembly 3 structure 5 basic material 7 arrangement 9 supply and application device 11 work station 13 working platform 15 laser device 17 laser beam 19 (supply) piston 21 basic material supply 23 application element 25 working plane 27 (working) piston 29 cylinder (of the working piston) 31 working end 33 cylinder (of the supply piston) 35 cavity 37 cavity wall 39 filling material 41 further assembly 43 insert element 45 spraying device 47 (basic material) supply container

Claims

Method for the additive production of a structure (3) in the form of a housing structure of a compressor housing of a turbocharger assembly (1) with increased containment safety, characterized bythe following steps: - provision of an arrangement (7) with a spraying device (45) which is connected to a base-material-supplying storage container (47), - spray application of the pulverulent metallic base material (5) by means of the spraying device (45) and subsequent laser processing, wherein the structure (3) is produced layer by layer additively, - provision of a structure cavity (35) with a cavity wall (37) with sufficient wall dimensions, - removal of remaining base material (5) from the partially finished structure cavity (35), - introduction of an insert element (43) into the cleared partial structure cavity, encapsulating the insert element (43) with the completion of the remaining structure cavity (35), wherein the encapsulation is effected by a cavity wall (37) which is completely additively manufactured and which completely surrounds the structure cavity (35).Method (1) according to Claim 1, characterized in that - a laser melting method is used in the context of additive manufacturing.Method according to one of the preceding claims, characterized in that - vibration damping and / or burst protection is effected on the turbocharger assembly (3) by means of the filled structural cavity (35).Turbocharger assembly (3) having a structure (3) in the form of a housing structure of a compressor housing, produced by a method according to one of the preceding claims.Turbocharger, characterized in that - the turbocharger has a turbocharger assembly (3) according to Claim 4.Turbocharger according to claim 5, characterised in that - the structural cavity (35) is a structural cavity of the compressor side or on the compressor side of the turbocharger.

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