PLANT FOR THE ADDITIVE MANUFACTURING OF THREE-DIMENSIONAL OBJECTS

Description

[0001] The invention relates to a system for the additive manufacturing of three-dimensional objects, comprising one or more workstations, each of which is set up to carry out at least one operation within the additive manufacturing of three-dimensional objects.

[0002] Systems for the additive manufacturing of three-dimensional objects are known in principle. Such systems typically comprise several workstations, each equipped to perform at least one operation within the additive manufacturing process of three-dimensional objects.

[0003] Sometimes it may be necessary to transport or temporarily store powder modules, such as build modules that define a build space in which the actual additive manufacturing of three-dimensional objects takes place, between different workstations of a system. In particular, an automatable or automated method for transporting and temporarily storing powder modules is desirable.

[0004] The invention is based on the objective of providing an improved system for the additive manufacturing of three-dimensional objects, particularly with regard to the possibility of automated transport and intermediate storage of powder modules.

[0005] DE 10 2014 016 718 A1 and DE 10 2012 002 955 A1 each disclose embodiments of additive manufacturing equipment.

[0006] EP 1 704 989 A1 discloses a device and a method for aligning a removable mold chamber in a process chamber of an additive manufacturing device.

[0007] The problem is solved by a system according to claim 1. The dependent claims relate to possible embodiments of the system.

[0008] The invention is defined by the appended claims. The system described herein ("system") is used for the additive manufacturing of three-dimensional objects, i.e., for example, technical components or technical component groups. The system comprises several workstations, each of which is configured to perform at least one operation within the additive manufacturing of three-dimensional objects ("objects"). Corresponding operations within the additive manufacturing of an object relate, on the one hand, to additive operations, i.e., additive build processes, in which an actual additive construction of an object takes place, in particular by successive layer-by-layer selective exposure and the associated successive layer-by-layer selective solidification of build material layers from a solidifiable build material by means of an energy beam, as well as to preparatory steps to be carried out before an additive operation or build process.Preparatory work processes carried out, i.e. cleaning, inerting and tempering processes of powder modules, as well as follow-up work processes to be carried out or carried out after an additive manufacturing or construction process, i.e. unpacking processes of additively manufactured objects from corresponding powder modules.

[0009] A first workstation, also referred to as a process station, set up for carrying out additive manufacturing processes can therefore include a device for the additive manufacturing of objects. The device is designed for the additive manufacturing of objects, i.e., for example, technical components or assemblies, by successive, layer-by-layer selective exposure and the associated successive, layer-by-layer selective solidification of layers of a solidifiable material. The material can be a particulate or powdered metal, plastic, and / or ceramic. The selective solidification of the respective layers of material to be selectively solidified is based on object-specific design data.The corresponding construction data describes the geometric and structural shape of the object to be additively manufactured and can, for example, include sliced ​​CAD data of the object. The device can be designed as an SLM device, i.e., a device for carrying out selective laser melting (SLM) processes, or as an SLS device, i.e., a device for carrying out selective laser sintering (SLS) processes.

[0010] The device comprises the functional components typically required for carrying out additive manufacturing processes. These include, in particular, a coating unit configured for the formation of selectively hardened layers of building material (in the build plane of the device), and an exposure unit configured for the selective exposure of these layers. The coating unit typically comprises several components, i.e., a coating element comprising a coating tool, in particular a blade-shaped one, and a guide for guiding the coating element along a defined path. The exposure unit also typically comprises several components, i.e., a beam generation unit for generating an energy or...The device comprises a laser beam, a beam deflection device (scanner device) for deflecting an energy or laser beam generated by the beam generation device onto an area of ​​a building material layer to be selectively hardened, and various optical elements, such as lens elements, objective elements, etc. The aforementioned functional components of the device are typically arranged or formed on or in a process chamber of the device, which is typically inertizable.

[0011] An optional additional (or second) workstation, also known as a post-processing station, designed for performing follow-up work processes, may include a device for unpacking an additively manufactured object. This device may be configured to unpack the object by removing the surrounding, typically non-solidified, building material. The device includes the functional components necessary for removing this surrounding, typically non-solidified, building material. This includes, in particular, a suction and / or blowing device designed to generate a suction and / or blowing flow by which the building material to be removed can be suctioned or blown away.

[0012] An optional additional (or third) workstation, also referred to as a preparation station, set up for carrying out preparatory work processes, may include a device for cleaning and / or inerting and / or temperature-controlling powder modules. The device may be configured for cleaning and / or inerting and / or temperature-controlling powder modules. Here, the device comprises the functional components required for cleaning and / or inerting and / or temperature-controlling powder modules. This includes, in particular, a cleaning device, which, for example, is configured to generate a cleaning flow for cleaning a powder chamber enclosed on the side of the powder module, or an inerting device, which is configured to generate an inert gas flow for inerting a powder chamber enclosed on the side of the powder module, or a temperature-control device, which is configured to temperature-control a powder module to a specific target temperature.

[0013] Regardless of their specific functional design, each workstation typically comprises its own housing structure, on or within which the functional components of the respective workstation are arranged or integrated. The workstations are thus to be viewed as separate, spatially and physically defined functional units of the system, defined by their respective housing structures, which can be positioned in various configurations relative to one another, e.g., in one or more building sections, particularly factory halls.

[0014] The system typically comprises multiple powder modules used in the additive manufacturing of three-dimensional objects. Each powder module is designed to receive and / or dispense build material and typically includes a powder chamber. The powder chamber defines a powder space that can be filled with build material. This powder space is bounded at least laterally by the walls (powder chamber walls) of the powder chamber, which is generally shaped like a hollow cuboid or hollow cylinder. At the bottom, the powder space is bounded by a support structure. The support structure is typically mounted to allow movement between two end positions, i.e., between an upper and a lower end position (relative to the height of the powder module), relative to the powder chamber. This movable mounting of the support structure enables movement, particularly linear movement, along a vertical axis.in a vertical direction of movement. The movable mounting of the support device is typically realized by a drive and / or actuator device coupled to it, in particular an (electric) motor.

[0015] Specifically, a powder module can be a build module in which the actual additive construction of objects takes place and which is successively filled layer by layer with selectively solidifying build material during additive manufacturing processes, or a dosing module through which build material is dosed into the process chamber during additive manufacturing processes, or a collection or overflow module which is filled with unsolidified build material during additive manufacturing processes.

[0016] The system further comprises at least one, typically several, freely positionable mobile storage unit(s) and at least one, typically several, driverless, freely movable mobile conveying unit(s). As will be shown below, the interaction of a storage unit and a conveying unit enables the realization of a modular transport and storage system that allows for the simultaneous storage and transport of powder modules.

[0017] Each storage unit comprises at least one rack-like storage device. The storage device includes at least one storage space, which is designed for storing at least one powder module, in particular for transporting the powder module between different workstations of the system. The storage space is formed by a frame structure that defines the external shape of the storage unit and comprises several frame sections, in particular wall-like sections. The frame structure includes first frame sections that delimit the storage space and second frame sections that allow the storage unit to be placed on a surface. The respective first frame sections can delimit the storage space, in particular, at the bottom, sides, and top. The first frame sections also define at least one access opening through which powder modules can be moved into and out of the storage space.Each second frame structure section can be designed like a foot, i.e., in particular as feet, so that these enable the storage unit to be placed stably on a surface.

[0018] Each conveying unit comprises at least one receiving device. The receiving device is designed to receive at least one mobile storage unit for the purpose of transporting the storage unit between different workstations of the system. Each conveying unit typically comprises at least one drive unit, in particular an (electric) motor, which can be supplied with energy via an energy storage device, i.e., a battery, and which is designed to generate a motive force, and a power transmission device coupled to the drive unit, which is designed to transmit the motive force generated by the drive unit to a surface to generate movement of the conveying unit relative to the surface. The power transmission device can specifically comprise a number of, for example,includes wheels, rollers or chains, via which the transmission of the driving force generated by the drive device to a surface can be realized in order to generate a movement of the conveying unit relative to the surface.

[0019] Each conveying unit can be moved automatically along different, i.e., in particular, arbitrarily configurable, movement paths. The configuration of each movement path can be fixed in a control unit of the respective conveying unit and can be changed via corresponding control information transmitted to the conveying unit, e.g., wirelessly. For the transmission, i.e., in particular for the reception, of corresponding control information, a conveying unit can be equipped with suitable, in particular wireless, communication interfaces. Such communication interfaces can also enable communication between conveying units; such communication includes, in particular, the bidirectional exchange of movement and / or position information relating to a current or future movement or positioning of a conveying unit.

[0020] A mounting device is arranged or formed on corresponding first frame structure sections, which is designed to hold at least one powder module in the storage space. The mounting device can be configured to hold a powder module movably relative to the frame structure, for which purpose the mounting device comprises bearing elements that enable a movable mounting of a powder module arranged in the mounting device relative to the frame structure.

[0021] The corresponding bearing elements can be, for example, sliding or roller bearing elements which interact with a powder module by forming a movable bearing, i.e., engage in working sections provided for this purpose on the powder module side, e.g., formed by recesses present on the powder module.

[0022] A first frame section of the frame structure, which defines the floor of the storage area, is positioned or designed at a distance from the ground, such that a space is formed between the surface of the first frame section facing the ground and the ground itself. The conveying unit can be dimensioned, particularly with regard to its height, such that it can move into the space beneath the first frame section defining the floor of the storage area. By moving the conveying unit into this space, i.e., beneath the first frame section defining the floor of the storage area, a receiving position can be defined in which the conveying unit can pick up the storage unit.

[0023] The receiving device can comprise at least one receiving element coupled to a lifting device, e.g., a plate-like or plate-shaped element. The receiving element is movably mounted between at least one, i.e., optionally also several, upper position(s) in which the receiving element is installed, such that the storage unit can be lifted or is lifted from a surface, and a lower position in which the receiving element is not installed, such that the storage unit can be lifted or is lifted from a surface. The lifting device can have a lifting drive, in particular an (electric) motor, i.e.,a lifting spindle or lifting cylinder drive, which is designed to generate a lifting force to move the receiving element into the respective positions.

[0024] Each workstation includes at least one transfer interface via which a powder module can be transferred from the workstation to the storage unit or a powder module from the storage unit to the workstation.

[0025] Each conveying unit can be moved (automatically) into a defined docking position, in which it is positioned relative to the transfer interface such that a powder module can be transferred from the workstation into the storage space of a storage unit mounted on the conveying unit. In the docking position, each conveying unit is typically positioned directly against the (exposed) outer surface of the workstation's housing that features the transfer interface.

[0026] The transfer interface can be closed by means of a locking device. The locking device can include a locking element which is movably mounted between an open position, in which the transfer interface is enabled for the transfer of a powder module from the workstation to a storage compartment of a storage unit or for the transfer of a powder module from the storage compartment of a storage unit to the workstation, and a closed position, in which the transfer interface is not enabled for the transfer of a powder module from the workstation to a storage compartment of a storage unit or for the transfer of a powder module from the storage compartment of a storage unit to the workstation. The movement of the locking element to the open or closed position, or vice versa, can be automated depending on the detection of a movement of a conveying unit into the docking position or vice versa.Depending on the system, the detection of a conveying unit moving into the docking position can be achieved. This detection can be accomplished using a suitable detection device. The detection device can, for example, include proximity or contact sensors, which can detect the movement of a conveying unit into the docking position or the detection of a conveying unit already in the docking position.

[0027] Each workstation can comprise a housing structure with a mounting device. The mounting device can be configured to hold a powder module movably relative to the housing structure along a transport path extending through the workstation. For this purpose, the mounting device includes bearing elements that enable the movable mounting of a powder module arranged in the mounting device relative to the housing structure. These bearing elements can, for example, be sliding or roller bearing elements that interact with a powder module to form a movable mounting, i.e., they engage in working sections provided for this purpose on the powder module, e.g., formed by recesses present on the powder module.The workstation can include a drive unit that interacts with the mounting device, by means of which a driving force can be generated to move a powder module along the transport path.

[0028] The respective mounting devices of the workstations and the respective mounting devices of the storage units, in particular the respective storage units mounted on a conveyor unit, are appropriately aligned with each other, so that a continuous transport path extending between the storage unit and the workstation is created, which makes it possible for powder modules held in the respective mounting devices to be easily transferred from a workstation to a storage unit, and vice versa.

[0029] For the same purpose, the respective mounting devices of the workstations and the respective mounting devices of the storage units are appropriately standardized or identically designed.

[0030] The invention is explained in more detail with reference to exemplary embodiments shown in the drawings. These show: Fig. 1 shows a schematic representation of a conveying unit and a storage unit of a system for the additive manufacturing of three-dimensional objects according to an exemplary embodiment; and Fig. 2 shows a schematic representation of a section of a system for the additive manufacturing of three-dimensional objects according to an exemplary embodiment.

[0031] Fig. 1 Figure 1 shows a schematic representation of a driverless mobile conveyor unit 3 and a freely positionable mobile storage unit 2 of a system 1 for the additive manufacturing of three-dimensional objects according to an exemplary embodiment.

[0032] Storage unit 2 comprises a rack-like storage system 4, which includes a storage space 5. This storage space 5 is designed for storing at least one powder module 6, i.e., for example, a construction module, and in particular for transporting the powder module 6 between different workstations 21 of Annex 1. The storage space 5 is formed by a frame structure 7, which defines the external shape of storage unit 2 and comprises several frame structure sections 7a and 7b, in particular wall-like sections. The frame structure 7 includes first frame structure sections 7a, which delimit storage space 5, and second frame structure sections 7b, which allow storage unit 2 to be placed on a surface. The first frame structure sections 7a delimit storage space 5 at the bottom, sides, and ceiling. The first frame structure sections 7a also define at least one access opening 8 through which powder modules 6 can be moved into and out of storage space 5.Each second frame structure section can be designed like a foot, i.e., in particular as feet, so that these enable the storage unit 2 to be placed stably on a surface.

[0033] A first frame structure section 7a of the frame structure 7, which limits the floor of the storage room 5, is arranged at a distance from the ground, so that a free space is formed between the surface of the first frame structure section 7a facing the ground and the ground.

[0034] A mounting device 9 is arranged or formed on the first frame structure sections 7a, i.e., on the inner sides of the frame structure sections 7a facing the storage space 5. This mounting device is designed to hold a powder module 6 in the storage space 5. The mounting device 9 is configured to hold the powder module 6 movably relative to the frame structure 7. For this purpose, the mounting device 9 comprises bearing elements 10, which enable the powder module 6 arranged in the mounting device 9 to be movably mounted relative to the frame structure 7. The bearing elements 10 can be, for example, sliding or roller bearing elements, which interact with a powder module 6 to form a movable mounting, i.e., engage in working sections provided for this purpose on the powder module side by recesses 11 present on the powder module side.The effective sections extend at least partially along two opposing wall sections of the powder module 6.

[0035] The conveying unit 3 comprises a receiving device 12, which is designed to receive a mobile storage unit 2 for the purpose of transporting the storage unit 2 between different workstations 21 of the system 1. The conveying unit 3 comprises a drive unit 13, in particular an (electric) motor, which is designed to generate a driving force, and a power transmission device 14 coupled to the drive unit 13, which is designed to transmit the driving force generated by the drive unit 13 to a surface to generate movement of the conveying unit 3 relative to the surface. The power transmission device 14 comprises a number of wheels, rollers, or chains via which the driving force can be transmitted to the surface.

[0036] As can be seen from the figure, the conveying unit 3, particularly with regard to its height, is dimensioned such that it can be moved into the space beneath the first frame structure section 7a, which defines the floor of the storage space 5. By moving the conveying unit 3 into this space, i.e., beneath the first frame structure section 7a, which defines the floor of the storage space 5, a receiving position is defined, as shown in the figure, in which the conveying unit 3 can receive the storage unit 2.

[0037] The receiving device 12 comprises a receiving element 16, e.g., plate-like or plate-shaped, coupled to a lifting device 15. The lifting device 15 comprises a lifting drive, in particular an (electric) motor (not shown), i.e., a lifting spindle or a lifting cylinder drive, which is configured to generate a lifting force for moving the receiving element 16. The receiving element 16 is to be engaged by means of the lifting device 15 between at least one, i.e., optionally also several, upper position(s) in which the receiving element 16 is configured, such that the bearing unit 2 can be lifted off the ground or...is lifted off, and in a lower position in which the receiving element 16 is not installed, is attached to the storage unit 2, in particular to the first frame structure section 7a which limits the floor of the storage space 5, in such a way that the storage unit 2 is lifted off the ground and is movably mounted.

[0038] The conveyor unit 3 can be moved automatically along different, i.e., in particular, arbitrarily configurable, movement paths. The configuration of each movement path can be permanently defined in a control unit (not shown) of the respective conveyor unit 3 and can be changed via corresponding control information transmitted to the conveyor unit 3, e.g., wirelessly. For the transmission, i.e., in particular for the reception, of corresponding control information, the conveyor unit 3 is equipped with suitable, in particular wireless, communication interfaces (not shown). Corresponding communication interfaces can also enable communication between conveyor units 3; such communication includes, in particular, the bidirectional exchange of movement and / or position information relating to a current or future movement or positioning of a conveyor unit 3.

[0039] Fig. 2 Figure 1 shows a schematic representation of a section of a system 1 for the additive manufacturing of three-dimensional objects according to an exemplary embodiment.

[0040] Annex 1 includes, although in Fig. 2 only a single workstation 21 is shown, several workstations 21, i.e. process stations set up for carrying out additive work processes, in which a device for the additive manufacturing of three-dimensional objects is arranged or designed.

[0041] The workstation 21 comprises a housing structure 18 with a mounting device 19, which is configured to hold a powder module 6 along a transport path extending through the workstation 21 (see double arrow) so that it can move relative to the housing structure 18. For this purpose, the mounting device 19 is equipped with bearing elements 20, which enable the powder module 6 arranged in the mounting device 19 to be moved relative to the housing structure 18. These bearing elements 20 can, for example, be sliding or roller bearing elements, which interact with a powder module 6 to form a movable mounting, i.e., they engage in the working sections provided for this purpose on the powder module side, e.g., formed by recesses 11 on the powder module side.The workstation 21 can include a drive unit (not shown) that interacts with the mounting device 19, by means of which a driving force can be generated to move a powder module 6 along the transport path.

[0042] Based on Fig. 2 It is evident that the respective holding devices 19 of the workstations 21 and the respective holding devices 9 of the storage units 2, in particular the respective storage units 2 mounted on a conveyor unit 3, are aligned with each other, so that a continuous transport path extending between storage unit 2 and workstation 21 is created, which makes it possible for powder modules 6 held in the respective holding devices 9, 19 to be easily transferred from a workstation 21 to a storage unit 2, and vice versa.

[0043] The workstation 21 includes at least one transfer interface 17, via which a powder module 6 is transferred from the workstation 21 to the storage unit 2 or - as in Fig. 2 shown - a powder module 6 can be transferred from storage unit 2 to workstation 21, i.e., can be transferred.

[0044] Each conveying unit 3 can be moved (automatically) into a defined docking position, in which the conveying unit 3 is moved relative to the transfer interface 17 of the workstation 21 in such a way that a powder module 6 can be transferred from the workstation 21 into the storage space 5 of the storage unit 2 mounted on the conveying unit 3, or vice versa, from the storage space 5 of the storage unit 2 mounted on the conveying unit 3 into the workstation 21. As described in Fig. 2As shown, each conveying unit 3 in the docking position is moved directly to or against the (exposed) outer surface of the housing construction 18 of the respective workstation 21 which has the transfer interface 17.

[0045] The transfer interface 17 of the workstation can be closed by means of a locking device (not shown). The locking device can comprise a locking element which is movably mounted between an open position, in which the transfer interface 17 is enabled for the transfer of a powder module 6 from the workstation 21 into a storage compartment 5 of a storage unit 2 or for the transfer of a powder module 6 from storage compartment 5 of a storage unit 2 into the workstation 21, and a closed position, in which the transfer interface 17 is not enabled for the transfer of a powder module 6 from the workstation 21 into a storage compartment 5 of a storage unit 2 or for the transfer of a powder module 6 from storage compartment 5 of a storage unit 2 into the workstation 21. Movement of the locking element into the open or closed position is prevented by the locking device.The movement of a conveyor unit 3 into the docking position, or vice versa, can be automated depending on the detection of its movement into the docking position or the detection of a conveyor unit 3 already in the docking position. This detection can be achieved by a suitable detection device (not shown). The detection device can, for example, include proximity or contact sensors that can detect the movement of a conveyor unit 3 into the docking position or the presence of a conveyor unit 3 already in the docking position.

[0046] Through the described interaction of storage unit 2 and conveyor unit 3, a modular transport and storage system is realized, which enables the simultaneous storage and transport of powder modules 6.

Claims

1. Plant (1) for the additive production of three-dimensional objects, comprising one or more workstations (21), which are set up to carry out at least one work process in the context of the additive production of three-dimensional objects, characterized by at least one freely positionable mobile storage unit (2), which comprises a shelf-like storage device (4), which comprises at least one storage room (5), which is equipped for storing at least one powder module (6) for the purpose of transporting the powder module (6) between different work stations (21) of the plant (1), at least one driverless freely movable mobile conveying unit (3) comprising a receiving device (12) which is set up to accommodate the at least one freely positionable mobile storage unit (2) for the purpose of transporting the storage unit (2) between different work stations (21) of the installation (1), wherein The storage space (5) of the at least one freely positionable mobile storage unit (2) is formed by a frame structure (7) defining the outer shape of the storage unit (2), comprising several frame structure sections (7a, 7b), wherein the frame structure (7) comprises first frame structure sections (7a), which limit the storage space (5), and second frame structure sections (7b), via which the storage unit (2) can be placed on a substrate, wherein at first frame structure portions (7a) a mounting device (9) is arranged or formed, which is arranged for holding at least one powder module (6) in the storage space (5), wherein a first frame structure portion (7a) limiting the floor of the storage space (5) is spaced away from a substrate or formed so that a free space is formed between the surface facing the substrate of the first frame structure portion (7a) and the substrate, wherein the conveying unit (3) is dimensioned such that it is movable into the free space below the floor of the storage space (5) limiting first frame structure portion (7a), wherein a respective workstation (21) comprises at least one transfer interface (17) via which a powder module (6) can be transferred from the workstation (21) to the storage unit (2) or a powder module (6) from the storage unit (2) to the workstation (21).

2. Plant according to claim 1, characterized in that the mounting device (9) is arranged to hold a powder module (6) movable relative to the frame structure (7), for which the mounting device (9) comprises bearing elements (10), which enable a movable storage of a powder module (6) arranged in the mounting device (9) relative to the frame structure (7).

3. Plant according to one of the preceding claims, characterized in that the receiving device (12) comprises at least one coupled to a lifting device (15) receiving element (16) which is mounted between at least one upper position in which the receiving element (16) is arranged to attack a bearing unit (2) in such a way that the bearing unit (2) is raised from a substrate, and a lower position in which the receiving element (16) is not arranged to attack a bearing unit (2) in such a way that the bearing unit (2) is raised from a substrate, movably mounted.

4. Plant according to one of the preceding claims, characterized in that the conveying unit (3) is movable in a defined docking position, in which the conveying unit (3) is moved so relative to the transfer interface (21) that a powder module (6) from the working station (21) into the storage space (5) of a storage unit (2) received on the conveying unit (3), or vice versa, is transferable.

5. Plant according to one of the preceding claims, characterized in that the transfer interface (17) can be closed via a closure means, wherein the closure means comprises a closure element which is released between an open position in which the transfer interface (17) for transferring a powder module (6) from the working station (21) to a storage room (5) of a storage unit (2) or for transferring a powder module (6) from the storage room (5) of a storage unit (2) to the working station (21) and a closing position in which the transfer interface (17) for transferring a powder module (6) from the working station (21) to a storage room (5) of a storage unit (2) or for transferring a powder module (6) from the storage room (5) of a storage unit (2) to the working station (21) is not released.

6. Plant according to one of the preceding claims, characterized in that a respective workstation (21) comprises a housing construction (18) with a mounting device (19) which is arranged to hold a powder module (6) along a transport path extending through the working station (21) movable relative to the housing construction (18), for which the mounting device (19) bearing elements (20) which enable a movable bearing of a powder module (6) arranged in the mounting device (19) relative to the housing construction (18), comprises.