DE102022118664A1 - Construction platform for additive repair of components and their use - Google Patents

Abstract

The invention relates to a construction platform (1) for the additive repair of components (90) and its use. The construction platform (1) comprises a platform (2) extending in a plane (XY) with fastening connections (3) for fastening the platform ( 2) in the installation space (110) of a system (100) for additive manufacturing in a clearly defined position. The platform (2) has positioning and/or fixing connections (4, 5) at defined distances from one another and from the fastening connections (3), with at least three positioning and/or fixing connections (4, 5) being variably provided on the positioning and/or fixing connections (4, 5). /or fixing elements (10, 20) for the precise positioning and fastening of components (90) to be repaired. When using the construction platform (1) according to the invention, it is fastened in the construction space (110) of a system (100) for additive manufacturing, so that the position of a component (90) attached to it in the installation space (110) is clear.

Description

The invention relates to a construction platform for the additive repair of components and its use.

Methods and systems for additive manufacturing are known in the prior art, in which successively applied metal powder layers are selectively melted into a solid material after solidification by a controlled laser beam according to a predetermined CAD model (“selective laser melting”; SLM). After all layers have been processed accordingly, the non-remelted powder can be removed and a metal component remains, which still needs to be reworked as required or can be used directly.

The technology of the additive manufacturing process with selective laser melting is also used for the additive repair of components. To do this, additional material is applied to existing components using the method described, for example to compensate for defects or wear on a component.

In order to be able to carry out appropriate repairs, the exact positioning or at least exact determination of the position of the component to be repaired on the construction platform of the manufacturing system is essential. This is the only way to ensure that material powder that is actually directly applied to the component to be repaired is melted by a laser beam and thus firmly connected to the component to be repaired.

It is known in the prior art to provide individual construction platforms for one or more components to be repaired, which are adapted to the individual component geometry in order to ensure the required exact positioning. For example, construction platforms are known on which a plurality of engine blades of an aircraft engine or a gas turbine can be mounted (cf. e.g. DE 10 2017 201 994 A1 ).

The disadvantage of this state of the art is that separate construction platforms have to be developed and manufactured for different components to be repaired. While this may still make sense for components such as engine blades, a large number of which are to be repaired regularly, it is often not useful for individual components that are only rarely repaired, even if such a component is suitable due to the presence of With suitable 3D models, repairs using systems for additive manufacturing are possible and even promise better results than manual repairs.

The object of the present invention is to create a way to additively repair components even without an individually developed construction platform.

This task is solved by a construction platform according to the main claim and its use according to the secondary claim. Advantageous further training is the subject of the dependent claims.

Accordingly, the invention relates to a construction platform for the additive repair of components comprising a platform extending in a plane with fastening connections for fastening the platform in the construction space of an additive manufacturing system in a clearly defined position, the platform having positioning and/or fixing connections in defined positions Distances from each other and from the fastening connections, with at least three positioning and / or fixing elements being variably attached to the positioning and / or fixing connections for the precise positioning and fastening of components to be repaired.

• - Anbringen von für das zu reparierende Bauteil geeigneten Positionier- und/oder Fixierelemente an Positionier- und/oder Fixieranschlüssen der Bauplattform, sodass die Lage eines damit fixierten Bauteils gegenüber den Befestigungsanschlüssen eindeutig ist;
• - Befestigen der Bauplattform in einer eindeutigen im Arbeitsraum einer Anlage zur additiven Fertigung mithilfe der Befestigungsanschlüsse;
• - Fixieren eines zu reparierenden Bauteils an der Bauplattform in der durch die Positionier- und/oder Fixierelemente vorgegebenen eindeutigen Lagen; und
• - Durchführen einer additiven Reparatur durch additiven Materialauftrag auf das zu reparierende Bauteil mithilfe der Anlage zur additiven Fertigung.

The invention further relates to the use of a construction platform according to the invention for the additive repair of components, with the steps:

• - Attaching positioning and/or fixing elements suitable for the component to be repaired to positioning and/or fixing connections of the construction platform, so that the position of a component fixed with it relative to the fastening connections is clear;
• - Fastening the build platform in a clear workspace of an additive manufacturing system using the fastening connections;
• - Fixing a component to be repaired to the construction platform in the unique positions specified by the positioning and/or fixing elements; and
• - Carrying out an additive repair by applying additive material to the component to be repaired using the additive manufacturing system.

First, some terms used in connection with the invention are explained.

A “positioning connection” is a design or shape of the platform to which a “positioning element” can optionally be attached. With a positioning element, the position of a component to be repaired on the platform can be determined in at least one direction parallel to the platform, for example by bringing the component into contact with the positioning element. The “positioning connection” is as follows to form that a positioning element attached to it is immovable at least in the direction in question.

A “fixing connection” is a design or shape of the platform to which a “fixing element” can optionally be attached. With a fixing element, the component to be repaired can be secured on the platform in a position predetermined by one or more positioning elements. In particular, the securing can be secured by frictional connection, for example using the construction platform and/or one or more positioning elements as a fixed counterpart in the sense of a clamping device.

It is possible for individual or all “positioning and fixing connections” to be designed as combined connections that meet the aforementioned requirements for positioning and fixing connections. Furthermore, it is possible that at least some of the positioning elements are also fixing elements at the same time, i.e. they can ensure both the determination of the position in at least one direction parallel to the platform and the fixation on the platform.

A position is “clear” if a component or component can only actually be attached in a defined position when the construction platform according to the invention is used properly and after attachment the position - apart from unavoidable technical tolerances - is to be viewed as defined and fixed. As a result, when fastening in a clear position, it is not necessary to verify which position a component or component actually occupies. Rather, it can be assumed that the actual position corresponds to the previously defined position.

The invention has recognized that through a construction platform which, on the one hand, has fastening connections with which the position of the construction platform in the construction space of an additive manufacturing system can be clearly determined (for example by attaching the construction platform above it to predetermined fastening areas in the construction space), as well Through positioning and/or fixing connections provided at defined distances from these fastening areas, components can be positioned in the installation space of an additive manufacturing system, which both offers the positioning accuracy for the component required for additive repair and can be used variably for different components. For this purpose, positioning and/or fixing elements can be variably arranged on the building platform at various positions predetermined by the positioning and/or fixing connections, with which a component can be fixed in a position defined in relation to the building board and its fastening connections, which means - at Appropriate arrangement in the installation space of an additive manufacturing system - also results in a defined position of the component in the installation space.

A corresponding defined position is required so that an additive repair of a component can be carried out efficiently using the additive manufacturing system. In particular, by using a construction platform according to the invention in an additive manufacturing system with a corresponding arrangement in its installation space, the position of a component to be repaired can be precisely determined in such a way that the control of the system required for the desired repair can be achieved solely on the basis of suitable 3-D Models of the component and the exact knowledge of its position defined by the construction platform in the construction space of the system can be done, in particular an intermediate step of detecting the position of the component in the construction space can be dispensed with.

In order to define a clear position of a component to be repaired relative to the construction platform, at least three positioning and/or fixing elements are provided according to the invention. By providing at least three corresponding elements, practically all components can be attached to the construction platform in a clear position without the need for special positioning and/or fixing elements. Rather, this is possible with standard positioning and/or fixing elements that can be used to position and fix any components. If individual components cannot be fixed in a clear position on the construction platform with three positioning and/or fixing elements, additional elements can of course be provided in a variable manner.

The position of the component to be repaired should be fixed in at least one direction parallel to the plane of the platform using a positioning element. In the simplest case, the positioning element can therefore be, for example, an elongated stop with a flat stop surface running perpendicular to the construction platform, which can define the position of the component in the direction perpendicular to the stop surface. For such an element, it is fundamentally sufficient if the positioning connection to which the positioning element is attached clearly determines its position in the direction mentioned - however, exact positioning of the stop in the plane of the stop surface is usually not important.

Alternatively and preferred for at least some of the positioning elements of the construction platform according to the invention, it is if the positioning element Conclusion for determining the position of a positioning element attached to it is designed in basically two non-parallel directions. A suitable embodiment of a corresponding positioning connection is a vertical hole in the platform, for example a blind hole, which may also be provided with an internal thread. A stop rod, for example, can be used as a positioning element, which, when attached to the end of a rod on a positioning connection - for example via a suitable external thread - extends in a direction perpendicular to the plane of the platform. The component to be repaired can then rest against the stop rod, whereby it is held - depending on the arrangement and design of the remaining positioning and fixing elements, possibly in two non-parallel directions.

With a fixing element, the component to be repaired should be secured in a position on the construction platform - at least partially predetermined by other positioning and fixing elements. For this purpose, fixing elements can be regularly brought from a fixing state to a loose state and vice versa.

In particular, clamping devices can be used as a fixing element, with which the component to be repaired can be clamped in a force-fitting manner between a clamping element and a counterpart that may not directly belong to the fixing element. In particular, the platform to which the fixing element is attached, as well as other positioning and/or fixing elements, can be used as a “counterpart”. The former - that is, that the platform is used as a counterpart - is preferred, as this reduces the risk of unwanted deformation or displacement of the other positioning and/or fixing elements and thus an unwanted change in the position of the components to be repaired when the frictional connection is established Fixing element is avoided or at least significantly reduced. The clamping device can be a spring-loaded clamping device or a clamping device with threaded spindles.

Even if fixing elements can in principle be attached to positioning connections to determine the position of a positioning and/or fixing element attached thereto in at least two directions, a corresponding location-accurate fixing of the fixing elements at least in two directions is generally not necessary. In order to enable greater flexibility when attaching different components to be repaired to the platform, it is preferred to design at least some of the fixing connections in such a way that positioning and/or fixing elements can be fastened in a variable position at least in a predetermined degree of freedom and a predetermined range is possible with it. In particular, individual fixing connections can be designed as T-slots, along which positioning and/or fixing elements can be fastened as desired using suitable sliding blocks.

So that the position of the construction platform in the installation space of a system for additive manufacturing is clear after attachment, it is preferred if at least some of the fastening connections are fitting holes for the precise positioning of the construction platform in the installation space of an additive manufacturing system. With the help of the fitting holes, the construction platform can be attached to an additive manufacturing system using bolts, for example, in a clear position at suitable fastening holes in the construction space.

To explain the use according to the invention, reference is made to the above statements. At least for the specific use in the additive repair of components in additive manufacturing systems, variably usable construction platforms, such as the present device according to the invention, are not known.

The system for additive manufacturing is preferably a system for selective laser melting, as is known from the prior art. With an appropriate system, metallic components in particular can be additively repaired using identical materials.

• 1a-d: ein erstes Ausführungsbeispiel einer erfindungsgemäßen Bauplattform für die additive Reparatur von Bauteilen in verschiedenen Stadien der Verwendung; und
• 2: ein zweites Ausführungsbeispiel einer erfindungsgemäßen Bauplattform für die additive Reparatur von Bauteilen.

The invention will now be described by way of example using advantageous embodiments with reference to the accompanying drawings. Show it:

• 1a-d : a first exemplary embodiment of a construction platform according to the invention for the additive repair of components in different stages of use; and
• 2 : a second exemplary embodiment of a construction platform according to the invention for the additive repair of components.

In 1a until 1c a first exemplary embodiment of a construction platform 1 according to the invention for the additive repair of components is shown in various states, as they also fundamentally occur when using the construction platform 1 according to the invention. The final use of the building platform 1 is in 1d sketched.

The construction platform 1 comprises a platform 2 which extends in one plane - in the exemplary embodiment shown in the XY plane. Four fastening connections 3 are provided on the platform in the form of continuous fitting holes, through the bolts for fastening in a clear position, for example in the installation space of a system 50 for additive manufacturing (cf. 1d ) can be attached.

Furthermore, the building platform 1 has four positioning connections 4 in the form of vertical Sachlock holes with internal threads, with which the position of positioning and / or fixing elements attached to it is determined in both the X and Y directions - therefore in two directions.

In addition, a large number of fixing connections 5 are provided in the form of T-slots, along which further components can be located using suitable sliding blocks 5 '(cf. 1b) Can be attached arbitrarily and in variable positions.

The positioning connections 4 and fixing connections 5 are each arranged at distances from one another and opposite the fastening connections 3. In the exemplary embodiment shown, the number, arrangement, design and distances of the positioning and fixing connections 4, 5 are selected such that a regular geometric pattern results.

Different positioning and fixing elements 10, 20 can be variably attached to the positioning and fixing connections 4, 5. The final selection and arrangement of at least three positioning and fixing connections 4, 5 takes place depending on the component 90 to be repaired and fixed by the construction platform 1 (cf. 1c ).

In the present example of use, three positioning elements 10 and one fixing element 20 are provided.

Two of the positioning elements 10 are stop rods 11, which have an external thread at one end, with which they are firmly and clearly fastened in two of the positioning connections 4. The third positioning element is a stop element 12 with a flat stop surface. The stop element 12 is attached to one of the fixing connections 5 using two sliding blocks 5 '(not visible). Due to the attachment to one of the fixing connections 5, the position of the stop element 12 is only clear in one direction - in the illustrated embodiment in the X direction - while the position in the other direction - i.e. in the Y direction or along the T-slot - is not clear. However, the latter is important for the clear position of component 90 (cf. 90 ) is irrelevant and therefore acceptable.

As a fixing element 20, a spring-loaded clamping element 21 is fastened in one of the fixing connections 5 using a sliding block 5 '. The clamping element 21 comprises a clamping element 22, with which a part of the component 90 - in the exemplary embodiment shown, a flange 91 (cf. 1d ) - clamped between clamping element 22 and platform 2, i.e. fixed in a non-positive manner.

For the precise positioning and attachment of a component to the according 1b equipped construction platform 1, the component 90 is first arranged on the platform 2 with the fixing element 20 loosened in such a way that the component 90 lies tightly against all positioning elements 10. The component is then fixed in the position defined in this way using the fixing element 20, which clamps the flange 91 of the component 90 in a non-positive manner. The positioning and fixing elements 10, 20 are arranged in such a way that the component 90 can actually only be arranged and fixed on the platform 2 in the position shown.

In 1d is the arrangement of the construction platform 1 according to 1a until 1c shown in the installation space 110 of a system 100 for additive manufacturing. We regularly clean the construction platform 1 after attaching the positioning and fixing elements 10, 20 to it (cf. 1b) , but before fixing a component 90 on the platform (cf. 1c ) in the construction space 110 of a corresponding system 100, the position of the construction platform 1 in the work space being clear by using the fastening connections 3 and suitable fastening options in the work space 110.

The system 100 for additive manufacturing is a system in which loose material is introduced into the construction space 110 in layers and is selectively hardened in order to create a three-dimensional object in layers or - as in the present case - material added to an already existing one , but for example a component in need of repair is applied.

The system 100 for additive manufacturing includes a construction space 110 on the bottom of which the construction platform 1 according to the invention is arranged and fastened in a defined, unique position. A laser scanner 101 is arranged above the construction platform 1 and the construction space 110, with which every point in the construction space 110 can be illuminated in a targeted manner. To control the laser scanner 101, a control device 103 connected to it via a data line 102 is provided.

Layers of powdery material (not shown) are successively introduced into the construction space 110 and are selectively remelted using the laser scanner 101 at coordinates specified for the respective layer.

In this respect, the system 100 corresponds to a system known from the prior art for additive manufacturing using selective laser melting. The use of corresponding systems for the additive repair of components is also generally known, as is the requirement for the components 90 to be repaired to be arranged in a clear position in the work space 110 or to be measured in a complex manner within the installation space 110 before the additive repair begins must. This is the only way to ensure that material remelted by the system 100 connects to the component 90 and that an additive repair can actually be successful.

With the construction platform 1 according to the invention, when used properly, almost any components 90 can be arranged and fixed in a previously defined, unique position in the work space 110, so that neither a complex measurement of each individual component nor a cost-intensive custom-made product is required to fix a specific component in a clear position in the work space 110 is required.

As a result, the control device 103 only needs to be supplied with suitable control data for the additive repair, which is provided by the computing unit 104 on the basis of 3-D models of the actual and target state of the component 90, as well as information about the clear position of the component 90 in work area 110 can be easily determined.

In 2 an alternative embodiment of a construction platform 1 according to the invention for the additive repair of components is shown. This exemplary embodiment compensates for that 1a-d , which is why only differences between the exemplary embodiments are pointed out below. Otherwise, reference is made to the above.

In the exemplary embodiment according to 2 There are no positioning connections 4 designed as vertical blind holes (cf. 1a-d ) intended. As a result, the stop rods 11 are also fastened as positioning elements 10 with sliding blocks 5 'in the fixing connections 5 designed as T-slots.

QUOTES INCLUDED IN THE DESCRIPTION

This list of documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102017201994 A1 [0005]

Claims (11)

Construction platform (1) for the additive repair of components (90) comprising a platform (2) extending in a plane (XY) with fastening connections (3) for fastening the platform (2) in the construction space (110) of a system (100). additive manufacturing in a clearly defined position, characterized in that the platform (2) has positioning and/or fixing connections (4, 5) at defined distances from one another and from the fastening connections (3), wherein at the positioning and/or fixing connections (4, 5) at least three positioning and/or fixing elements (10, 20) are variably attached for the precise positioning and fastening of components (90) to be repaired. construction platform Claim 1 , characterized in that the positioning and/or fixing connections (4, 5) are designed and arranged to form a regular geometric pattern. Building platform according to one of the preceding claims, characterized in that at least one positioning connection (4) is designed to determine the position of a positioning and/or fixing element (10, 20) attached thereto in at least two directions. construction platform Claim 3 , characterized in that at least one positioning connection (4) for determining the position of a positioning and/or fixing element (10,20) attached to it in at least two directions is designed as a vertical bore in the platform (2), preferably with an internal thread. Building platform according to one of the preceding claims, characterized in that at least one positioning element (10) is designed as a stop rod (11). Building platform according to one of the preceding claims, characterized in that at least some of the fixing connections (5) are designed for positionally variable fastening of positioning and/or fixing elements (10, 20) thereon. construction platform Claim 6 , characterized in that at least some of the fixing connections (5) are designed as T-slots, along which positioning and / or fixing elements can be fastened in any way using suitable sliding blocks (5`). Building platform according to one of the preceding claims, characterized in that at least one fixing element (20) is designed as a clamping element (21) for clamping a component (90) between the clamping element (22) of the clamping element (21) and the platform (2). Building platform according to one of the preceding claims, characterized in that at least some of the fastening connections (3) are fitting holes for fastening the building platform (1) in a precise position in the building space (110) of a system (100) for additive manufacturing. Use of a construction platform (1) according to one of the preceding claims for the additive repair of components, characterized by the steps: - attaching at least three positioning and / or fixing elements (10, 20) suitable for the component (90) to be repaired to positioning and/or fixing connections (4, 5) of the building platform (1), so that the position of a component (90) fixed therewith is clear relative to the fastening connections (3); - Fastening the construction platform (1) in a clear position in the work space (110) of a system (100) for additive manufacturing using the fastening connections (3); - Fixing a component (90) to be repaired to the construction platform (1) in the unique position specified by the positioning and/or fixing elements (4, 5); and - carrying out an additive repair by applying additive material to the component (90) to be repaired using the additive manufacturing system (100). Use after Claim 10 , characterized in that the system (100) for additive manufacturing is a system for selective laser melting.

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