Abstract
The invention relates to an apparatus for laser-deposition welding with multiple laser-deposition welding heads and to a method for operating such an apparatus comprising a laser-deposition welding unit with multiple laser-welding heads arranged thereon for the (quasi-) simultaneous depositing of material (M) onto a surface of a component and also comprising one or more conveying units for supplying the laser-deposition welding heads with the material (M) to be applied and further comprising one or more laser-radiation sources for supplying the laser-deposition welding heads with laser radiation (L) for carrying out the laser-deposition welding.
Claims
1-22. (canceled)
23. An apparatus for laser-deposition welding, having a laser-deposition welding unit with multiple laser-deposition welding heads arranged thereon for (quasi-)simultaneous depositing of material (M) onto a surface of a component and having one or more conveying units for supplying the laser-deposition welding heads with the material (M) to be applied and having one or more laser beam sources for supplying the laser-deposition welding heads with laser radiation (L) for carrying out the laser-deposition welding.
24. The apparatus according to claim 23, wherein the laser-deposition welding heads each produce a laser welding spot on the surface of the component, and adjacent laser welding spots have a first offset (R1) from one another perpendicular to a feed direction (VR) of the laser welding spots on the surface of the component.
25. The apparatus according to claim 24, wherein the laser welding spots produce deposition welding tracks (MS) with a material width (MB) along the feed direction (VR) on the surface, in which welding tracks the first offset (R1) of adjacent laser welding spots is between 10% and 90%, preferably between 40% and 60%, most preferably 50%, of the material width (MB) of the deposition welding track (MS).
26. The apparatus according to claim 24, wherein the adjacent laser welding spots on the surface of the component have a second offset (R2) from one another in the feed direction (VR).
27. The apparatus according to claim 26, wherein the second offset (R2) is set in such a way that temperature profiles induced by the laser welding spots on the surface overlap to such an extent that the material (M) in an overlap region of adjacent deposition welding tracks (MS) still has a residual heat that is usable/admissible for the process.
28. The apparatus according to claim 23, wherein the apparatus is configured, after an areal deposition of the material (M) as a preceding layer (S1) onto the surface of the component, to guide the laser-deposition welding heads in such a way that a further areal deposition of the material (M) as a subsequent layer (S1) onto the preceding layer (S1) is carried out in order to deposit the material as a multilayer system (SS).
29. The apparatus according to claim 28, wherein the deposition welding tracks (MS) of the subsequent layer (S2) are deposited onto the preceding layer (S1) with a third offset (R3) perpendicular to the feed direction (VR) relative to the underlying deposition welding tracks (MS) of the preceding layer (S1).
30. The apparatus according to claim 29, wherein the deposited layers (S1, S2) have a varying layer thickness with a smaller layer thickness (SD1) and a larger layer thickness (SD2), wherein the third offset (R3) of the deposition welding tracks of superimposed layers (S1, S2) is set in such a way that the larger layer thicknesses (SD2) of the subsequent layer are arranged above the smaller layer thicknesses (SD1) of the preceding layer (S1).
31. The apparatus according to claim 23, wherein the apparatus is configured to supply, by suitable control of the conveying units, the laser deposition welding heads with different materials for deposition onto the surface of the component.
32. The apparatus according to claim 31, wherein the control is carried out in such a way that layers (S1, S2) of a multilayer system (SS) consist of different materials (M), with first layers (S1) of a first material (M1) and second layers (S2) of a second material (M2).
33. The apparatus according to claim 23, wherein the laser-deposition welding unit is, in order to perform a movement relative to the surface of the component, arranged in the apparatus so as to be movable, preferably by means of a movement unit.
34. The apparatus according to claim 23, wherein the laser-deposition welding heads are, in order to perform a movement relative to one another, arranged in the apparatus so as to be movable, preferably by means of a laser-deposition welding head movement unit.
35. The apparatus according to claim 23, wherein the apparatus comprises a control unit designed to suitably control at least the movements of the laser-deposition welding unit and/or of the laser-deposition welding heads and/or the conveying units and/or of the laser beam sources in order to carry out the laser-deposition welding, for which purpose the control unit is suitably connected to these components.
36. A method for operating an apparatus for laser-deposition welding according to claim 23, having a laser-deposition welding unit with multiple laser-deposition welding heads arranged thereon, comprising the step of (quasi-)simultaneously depositing material (M) onto a surface of a component.
37. The method according to claim 36, wherein the laser-deposition welding heads each produce a laser welding spot on the surface of the component, comprising the further step of moving adjacent laser welding spots with a first offset (R1) from one another perpendicular to a feed direction (VR) of the laser welding spots on the surface of the component.
38. The method according to claim 37, comprising the further step of moving adjacent laser welding spots on the surface of the component with a second offset (R2) from one another in the feed direction (VR).
39. The method according to claim 36, comprising the further step of controlling at least the movements of the laser-deposition welding unit and/or of the laser-deposition welding heads and/or of the conveying units and/or of the laser beam sources in order to carry out the laser-deposition welding by means of a control unit suitably connected to these components.
40. The method according to claim 36, comprising the further step of depositing a multilayer system (SS) onto the surface of the component by suitably guiding the laser-deposition welding heads of the apparatus, in which, after an areal deposition of the material (M) as a preceding layer (S1) onto the surface of the component, a further areal deposition of the material (M) as a subsequent layer (S1) onto the preceding layer (S1) takes place.
41. The method according to claim 40, wherein the deposited layers (S1, S2) of the multilayer system (S) have a varying layer thickness with a smaller layer thickness (SD1) and a larger layer thickness (SD2), comprising the further step of setting a third offset (R3) perpendicular to the feed direction (VR) between deposition welding tracks (MS) of the subsequent layer (S2) and underlying deposition welding tracks (MS) of the preceding layer (S1) such that the larger layer thicknesses (SD2) of the subsequent layer are arranged above the smaller layer thicknesses (SD1) of the preceding layer (S1).
42. The method according to claim 40, comprising the further step of controlling the conveying units for the laser-deposition welding heads in such a way that the layers (S1, S2) of the multilayer system (SS) consist of different materials (M), with first layers (S1) of a first material (M1) and second layers (S2) of a second material (M2).
43. The method according to claim 36, wherein the component, preferably a brake disc, comprises a circular surface which has a rotation axis (D) and onto which the material is deposited, comprising the further steps of rotating the circular surface about the rotation axis (D) under the laser-deposition welding heads such that their laser welding spots on the circular surface would circularly run over the surface when the laser-deposition welding heads are at rest; and moving the laser-deposition welding heads in the direction of the rotation axis (D) such that the material (M) is deposited in spiral deposition welding tracks (MS) by area of the circular surface.
44. The method according to claim 36, wherein the component, preferably a shaft, comprises a rotationally symmetrical surface which has a rotation axis (D) and onto which the material is deposited, comprising the further steps of rotating the rotationally symmetrical surface, preferably the cylindrical surface of the shaft, about the rotation axis (D) under the laser-deposition welding heads such that their laser welding spots on the rotationally symmetrical surface would circularly run over the surface when the laser-deposition welding heads are at rest; and moving the laser-deposition welding heads in the feed direction (VR) parallel to the rotation axis (D) such that the material (M) is deposited in spiral deposition welding tracks (MS) by area on the rotationally symmetrical surface.
Description
BRIEF DESCRIPTION OF THE FIGURES
[0044] These and other aspects of the invention are shown in detail in the figures as follows.
[0045] FIG. 1: an embodiment of the apparatus according to the invention;
[0046] FIG. 2: a top view of a brake disc as an example of a circular component having the dynamic behaviour of the laser welding spots during laser-deposition welding of an apparatus according to the invention, in this embodiment with four laser-deposition welding heads;
[0047] FIG. 3: a perspective view of a shaft as an example of a rotationally symmetrical component with the dynamic behaviour of the laser-deposition welding spots during laser-deposition welding of an apparatus according to the invention in this embodiment with three laser-deposition welding heads;
[0048] FIG. 4: an exemplary side view of deposition welding tracks deposited by area using the apparatus according to the invention, (a) as a single layer, (b) as a single layer with a larger first offset compared to FIG. 4a, and (c) of a multilayer system; and
[0049] FIG. 5: an embodiment of the method according to the invention for operating the apparatus according to the invention.
DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS
[0050] FIG. 1 shows an embodiment of the apparatus 1 for laser-deposition welding according to the invention, having a laser-deposition welding unit 2 with, in this case for example, two laser-deposition welding heads 3 arranged thereon for the (quasi-)simultaneous depositing of material M onto a surface 41 of a component 4 along a respective deposition welding track MS per laser-deposition welding head 3, and having one or more conveying units 5 (shown here symbolically as a unit 5) for supplying the laser-deposition welding heads 3 with the material M to be applied, and having one or more laser beam sources 6 (shown here symbolically as a unit 6) for supplying the laser-deposition welding heads 3 with laser radiation L for carrying out the laser-deposition welding, and having a control unit 7 designed to suitably control at least the movements of the laser-deposition welding unit 2 and/or of the laser-deposition welding heads 3 and/or the conveying units 5 and/or of the laser beam sources 6 in order to carry out the laser-deposition welding, for which purpose the control unit 7 is suitably connected to these components, for example via data lines or other connecting means, indicated by the solid lines. The laser-deposition welding head 3 comprises an optical system for guiding the beam of laser radiation, a powder feed nozzle including an adjustment unit and optionally a local protective gas supply. Suitable laser beam sources for laser-deposition welding are known. The two laser-deposition welding heads 3 shown here each produce a laser welding spot 31 on the original surface 41 of the component 4 and accordingly on the deposition welding track MS of the previously positioned laser-deposition welding head 3, wherein the two laser welding spots 31, relative to the surface 41 of the component 4, have a second offset R2 from one another in the feed direction VR. In this respect, the original surface 41 and the surface of the first deposition welding track MS are both referred to as the surface of the component 41 onto which the material is deposited by means of the deposition welding track MS. Furthermore, although not explicitly shown here, the two laser welding spots 31 may have a first offset R1 from one another perpendicular to a feed direction VR of the laser welding spots 31 on the surface 41 of the component 4. The apparatus 1 can be configured to supply, by suitable control of the conveying units 5, the laser-deposition welding heads 3 with different materials for deposition onto the surface 41 of the component 4. In this case, the apparatus 1 comprises one conveying unit 5 for each different material. To coat the entire area of the component 4 with multiple deposition welding tracks MS arranged next to one another, the laser-deposition welding unit 2 can, in order to perform a movement relative to the surface 41 of the component 4, be arranged in the apparatus 1 so as to be movable, preferably by means of a movement unit. The skilled person is capable of using suitable movement units for the respective components and the material depositions to be produced. In this respect, the laser-deposition welding heads 3 can additionally be arranged in the apparatus 1 so as to be movable relative to one another in order to perform a movement, preferably by means of a laser-deposition welding head movement unit, for which the same applies. The components to be processed can have different geometries and sizes and be made from different materials. Depending on the component to be processed, the number of laser-deposition welding heads used can vary, although at least two laser-deposition welding heads are always used.
[0051] FIG. 2 shows a top view of a brake disc 42 as an example of a circular component 4 having the dynamic behaviour of the laser welding spots 31 during laser-deposition welding of an apparatus 1 according to the invention, in this embodiment with four laser-deposition welding heads 3 for (quasi-)simultaneous deposition 110 of material M onto the surface 41 of a component 4. In other embodiments, the number of laser-deposition welding heads may also be two, three, five, six or more, wherein the maximum number is limited only by the size of the laser-deposition welding heads 3 and the available space above the component 4. The four laser-deposition welding heads 3 shown here each produce a laser welding spot 31 on the surface 41 of the component 4, wherein the four laser welding spots 31 have a first offset R1 from one another perpendicular to a feed direction VR of the laser welding spots 31 on the surface 41 of the component 4 and are moved with this first offset over the surface 41 during the method. The laser welding spots 31 thus produce deposition welding tracks MS with a material width MB along the feed direction VR on the surface 41, in which welding tracks the first offset R1 of adjacent laser welding spots 31 is between 10% and 90%, preferably between 40% and 60%, most preferably 50%, of the material width MB of the deposition welding track MS. Furthermore, the adjacent laser welding spots 31 on the surface 41 of the component 4 have a second offset R2 from one another in the feed direction VR, which here is in each case a quarter of the circumference of the brake disc 42 for the respective radial distance of the laser welding spot 31 from the centre point of the brake disc 42, through which the rotation axis D of the brake disc 52 as component 4 passes. The second offset R2 is in this case set in such a way that temperature profiles induced by the laser welding spots 31 on the surface 41 overlap to such an extent that the material M in an overlap region of adjacent deposition welding tracks MS still has a residual heat that is usable/admissible for the process. A usable/admissible residual heat would be, for example, a temperature at which the material of one or more adjacent deposition welding tracks MS can still deform due to the temperature induced in the laser welding spot of the deposition welding track MS just deposited. The brake disc 42 could be mounted by means of the screw holes 42a on a turntable, by which the brake disc 42 is rotated about the rotation axis D. In order to deposit the material M onto the brake disc 42, the circular surface 41 is rotated 180 about the rotation axis D under the laser-deposition welding heads 3 such that their laser welding spots 31 on the circular surface 41 would circularly run over the surface 41 when the laser-deposition welding heads 3 are at rest; and simultaneously the laser-deposition welding heads 3 are moved 190 in the direction of the rotation axis D such that the material M is deposited in spiral-shaped adjoining or partially overlapping deposition welding tracks MS by area on the circular surface 41.
[0052] FIG. 3 shows a perspective view of a shaft 43 as an example of a rotationally symmetrical component 4 having the dynamic behaviour of the laser welding spots 31 during laser-deposition welding of an apparatus 1 according to the invention, in this embodiment with three laser-deposition welding heads 3, which are not shown in detail here for clarity reasons, for (quasi-)simultaneous deposition 110 of material M onto the surface 41 of the shaft 43. In other embodiments, the number of laser-deposition welding heads may also be two, four, five or more, wherein the maximum number is limited only by the size of the laser-deposition welding heads 3 and the available space above the component 4. The three laser-deposition welding heads 3 each produce a laser welding spot 31 on the surface 41 of the component 4 and adjacent laser welding spots 31 have a first offset R1 from one another perpendicular to a feed direction VR of the laser welding spots 31 on the surface 41 of the component 4, in which the first offset R1 of adjacent laser welding spots 31 is between 10% and 90%, preferably between 40% and 60%, most preferably 50%, of the material width MB of the deposition welding track MS. Likewise, the adjacent laser welding spots 31 on the surface 41 of the component 4 have a second offset R2 from one another in the feed direction VR, which offset is set in such a way that temperature profiles induced by the laser welding spots 31 on the surface 41 overlap to such an extent that the material M in an overlap region of adjacent deposition welding tracks MS still has a residual heat that is usable/admissible for the process; the same applies here as for FIG. 2. In order to deposit the material M, the rotationally symmetrical surface 41, which in this case is the cylindrical surface of the shaft 43, is in this case rotated 200 about the rotation axis D under the laser-deposition welding heads 3 such that their laser welding spots 31 on the rotationally symmetrical surface 41 would circularly run over the surface 41 when the laser-deposition welding heads 3 are at rest; and the laser-deposition welding heads 3 are moved 210 in the feed direction VR parallel to the rotation axis D such that the material M is deposited in spiral-shaped deposition welding tracks MS by area on the rotationally symmetrical surface 41. The preceding movement 210 is a relative movement, wherein either the laser-deposition welding heads 3 (in any desired number) are moved over the shaft 43 or the shaft 43 is moved under the laser-deposition welding heads 3. For this purpose, the shaft 43 can be clamped in a corresponding movement unit for rotation and, optionally, for longitudinal movement.
[0053] FIG. 4 shows an exemplary side view of deposition welding tracks MS deposited by area using the apparatus according to the invention, (a) as a single layer, (b) as a single layer with a larger first offset R1 compared to FIG. 4a, and (c) of a multilayer system composed of the layers S1 and S2 as a two-layer system, by way of example. In FIG. 4c, the laser-deposition welding heads 3 have been guided in such a way that, after the material M was deposited as the preceding layer S1 by area on the surface 41 of the component 4, a further areal deposition of the material M as the subsequent layer S1 onto the preceding layer S1 was carried out in order to deposit the material as a two-layer system SS, wherein the deposition welding tracks MS of the subsequent layer S2 have a third offset R3 perpendicular to the feed direction VR relative to the underlying deposition welding tracks MS of the preceding layer S1. Since the deposited layers S1, S2 have a varying layer thickness with a smaller layer thickness SD1 and a larger layer thickness SD2, the third offset R3 of the deposition welding tracks of the two superimposed layers S1, S2 was set in such a way that the larger layer thicknesses SD2 of the subsequent layer are arranged above the smaller layer thicknesses SD1 of the preceding layer S1 in order to minimise the resulting undulation of the surface of the two-layer system. The same applies to multilayer systems composed of more than two layers. In this respect, the layers S1, S2 of a multilayer system SS can consist of different materials M, for example with first layers S1 made of a first material M1 and second layers S2 made of a second material M2 in the case of the two-layer system shown here.
[0054] FIG. 5 shows an embodiment of the method 100 according to the invention for operating an apparatus 1 for laser-deposition welding according to the invention, having a laser-deposition welding unit 2 with multiple laser-deposition welding heads 3 arranged thereon, comprising the step of (quasi-)simultaneously depositing 110 material M onto a surface 41 of a component 4. In this case, the laser-deposition welding heads 3 each produce a laser welding spot 31 on the surface 41 of the component 4. Adjacent laser welding spots 31 can be moved 120 with a first offset R1 from one another perpendicular to a feed direction VR of the laser welding spots 31 on the surface 41 of the component 4. Likewise, adjacent laser welding spots 31 on the surface 41 of the component 4 can be moved 130 with a second offset R2 from one another in the feed direction VR. In this case, the movements of the laser-deposition welding unit 2 and/or of the laser-deposition welding heads 3 and/or of the conveyor units 5 and/or of the laser beam sources 6 can be controlled 140 in order to carry out the laser-deposition welding by means of a control unit 7 suitably connected to these components 2, 3, 5, 6. A multilayer system SS can be deposited 150 onto the surface 41 of the component 4 by suitably guiding the laser-deposition welding heads 3 of the apparatus 1, wherein, after an areal deposition of the material M as a preceding layer S1 onto the surface 41 of the component 4, a further areal deposition of the material M as a subsequent layer S1 onto the preceding layer S1 takes place. In this case, the deposited layers S1, S2 of the multilayer system 5 can have a varying layer thickness, with a smaller layer thickness SD1 and a larger layer thickness SD2. A third offset R3 perpendicular to the feed direction VR can be set 160 between deposition welding tracks MS of the subsequent layer S2 and underlying deposition welding tracks MS of the preceding layer S1, such that the greater layer thicknesses SD2 of the subsequent layer are arranged above the smaller layer thicknesses SD1 of the preceding layer S1. In this case, the conveying units 5 for the laser-deposition welding heads 3 can be controlled 170 in such a way that the layers S1, S2 of the multilayer system SS consist of different materials M, with first layers S1 of a first material M1 and second layers S2 of a second material M2. In an embodiment where the component 4, preferably a brake disc 42, comprises a circular surface 41 which has a rotation axis D and onto which the material is deposited, the method 100 comprises the further steps of rotating 180 the circular surface 41 about the rotation axis D under the laser-deposition welding heads 3 such that their laser welding spots 31 on the circular surface 41 would circularly run over the surface 41 when the laser-deposition welding heads 3 are at rest; and moving 190 the laser-deposition welding heads 3 in the direction of the rotation axis D such that the material M is deposited in spiral deposition welding tracks MS by area on the circular surface 41. In a further embodiment where the component 4, preferably a shaft 43, comprises a rotationally symmetrical surface 41 which has a rotation axis D and onto which the material is deposited, the method 100 comprises the further steps of rotating 200 the rotationally symmetrical surface 41, preferably the cylindrical surface of the shaft 43, about the rotation axis D under the laser-deposition welding heads 3 such that their laser welding spots 31 on the rotationally symmetrical surface 41 would circularly run over the surface 41 when the laser-deposition welding heads 3 are at rest; and moving 210 the laser-deposition welding heads 3 in the feed direction VR parallel to the rotation axis D such that the material M is deposited in spiral deposition welding tracks MS by area on the rotationally symmetrical surface 41.
LIST OF REFERENCE SIGNS
[0055] 1 apparatus for laser-deposition welding according to the invention [0056] 2 laser-deposition welding unit [0057] 3 laser-deposition welding head [0058] 31 laser welding spot [0059] 4 component [0060] 41 surface of the component onto which the material is deposited [0061] 42 brake disc [0062] 42a screw holes [0063] 43 shaft [0064] conveying unit [0065] 6 laser beam source [0066] 7 control unit [0067] 100 method according to the invention for operating an apparatus for laser-deposition welding [0068] 110 (quasi-)simultaneous deposition of material (M) onto a surface of a component by means of multiple laser-deposition welding heads [0069] 120 moving adjacent laser welding spots with a first offset from one another perpendicular to a feed direction of the laser welding spots [0070] 130 moving adjacent laser welding spots with a second offset from one another in the feed direction [0071] 140 controlling at least the movements of the laser-deposition welding unit and/or of the laser-deposition welding heads and of at least the conveying units and/or laser beam sources by means of a suitably connected control unit [0072] 150 depositing a multilayer system onto the surface of the component [0073] 160 setting a third offset perpendicular to the feed direction between deposition welding tracks of the subsequent layer and underlying deposition welding tracks of the preceding layer [0074] 170 controlling the conveying units for the laser-deposition welding heads in such a way that the layers of the multilayer system consist of different materials [0075] 180 rotating the circular surface about the rotation axis of the surface under the laser-deposition welding heads [0076] 190 moving the laser-deposition welding heads in the direction of the rotation axis of the surface [0077] 200 rotating the rotationally symmetrical surface about the rotation axis under the laser-deposition welding heads [0078] 210 moving the laser-deposition welding heads in the feed direction parallel to the rotation axis [0079] D rotation axis of the component during laser-deposition welding [0080] M material to be deposited [0081] MB material width of the deposition welding track [0082] MS deposition welding track of the applied material on the surface of the component [0083] L laser radiation [0084] R1 first offset of adjacent laser welding spots from one another perpendicular to the feed direction [0085] R2 second offset of adjacent laser welding spots from one another in the feed direction [0086] R3 third offset of the deposition welding tracks of superimposed layers perpendicular to the feed direction [0087] RB direction of rotation of the component [0088] S1 first layer of material deposited by area [0089] S2 second layer of material deposited by area [0090] SD1 smaller layer thicknesses [0091] SD2 larger layer thicknesses [0092] SS multilayer system [0093] VR feed direction
