TRANSMISSION ELEMENT AND METHOD FOR PRODUCING A TRANSMISSION ELEMENT

Abstract

A toothed transmission element includes a partial region formed with a first material, teeth defining an edge region which is formed additively with a second material having a hardness which is greater than a hardness of the first material, and a third material located between the first material and the second material, wherein a hardness decreases stepwise along a section leading from the edge region to the partial region.

Claims

1-14. (canceled)

15. A toothed transmission element, comprising: a partial region formed with a first material; an edge region formed additively with a second material having a hardness which is greater than a hardness of the first material; and a third material located between the first material and the second material, wherein a hardness decreases stepwise along a section leading from the edge region to the partial region.

16. The transmission element of claim 15, wherein the hardness is a Vickers hardness, with a difference in the Vickers hardness of the second material and the Vickers hardness of the first material is at least 100, preferably at least 200, ideally at least 400, degrees of hardness, and in particular the second material has a Vickers hardness of at least 500, preferably at least 600, preferably at least 780 HV, and/or the first material has a Vickers hardness of at most 400 HV, preferably at most 350 HV.

17. The transmission element of claim 15, further comprising at least one or more teeth defining the edge region, wherein at least one or more, preferably all, of the teeth has or have the edge region formed additively with the second material.

18. The transmission element of claim 15, wherein the partial region is formed additively or the partial region is formed through primary forming, preferably casting, forming, preferably forging, subtractively, in particular by machining.

19. The transmission element of claim 15, wherein the first material has a ductility which is higher than a ductility of the second material or the second material has an internal compressive stress which is greater than the internal compressive stress of the first material.

20. The transmission element of claim 15, constructed in the form of a gearwheel or a rack.

21. The transmission element of claim 15, wherein the third material, between the first and second material is formed additively.

22. The transmission element of claim 15, wherein the first material is formed with or from case-hardened steel and/or nickel-based alloy.

23. The transmission element of claim 15, wherein the second material is formed with or from hard metal, preferably tungsten carbide, and/or a nickel-based alloy which preferably has long-term thermal stability at at least 250 degrees Celsius.

24. The transmission element of claim 15, wherein at least the second material is formed by laser deposition welding, in particular laser wire deposition welding or laser powder deposition welding, and/or thermal spraying and/or cold gas spraying and/or arc deposition welding and/or by a powder bed process, in particular laser beam melting and/or selective laser melting and/or electron beam melting.

25. A method for producing a transmission element as set forth in claim 15, said method comprising: forming a partial region with a first material; forming an edge region which is formed additively with a second material by laser deposition welding, in particular laser wire deposition welding, and/or thermal spraying and/or arc deposition welding and/or a powder bed process and/or selective laser melting, with the second material having a hardness which is greater than a hardness of the first material, with the second material; and forming a third material between the first material and the second material, wherein a hardness decreases stepwise along a section leading from the edge region to the partial region.

26. A transmission, comprising a transmission element as set forth in claim 15.

27. A machine, in particular an electric machine, preferably a generator and/or motor and/or electric motor, comprising a transmission as set forth in claim 26.

28. A turbine, in particular a wind turbine and/or gas turbine and/or aircraft gas turbine, comprising a transmission as set forth in claim 26 or an electric machine comprising said transmission.

Description

[0031] The single FIG. 1 of the drawing shows a transmission element according to the invention in the form of a gearwheel schematically in a basic diagram in cross section.

[0032] The transmission element according to the invention in the form of a gearwheel 10 which is illustrated in the drawing is part of an electric machine 20 according to the invention in the form of a generator of a wind turbine 30 according to the invention. In further exemplary embodiments, which are not specifically illustrated, the gearwheel 10 is part of a transmission of a gas turbine or of an aircraft gas turbine or of a motor and otherwise corresponds to the exemplary embodiment illustrated.

[0033] The gear wheel 10 is rotatable in the plane of the drawing of Fig 1, i.e. about an axis of rotation (not explicitly shown) perpendicular to the plane of the drawing. As shown in FIG. 1. the gearwheel 10 is toothed with teeth 40 arranged on the outer circumference around this axis of rotation. The teeth 40 extend radially outward from a substantially circular gearwheel core 50, i.e. in the radial direction R.

[0034] According to the invention, the gearwheel 10 is formed as follows: First, the circular gearwheel core 50 is produced by means of primary forming, by means of casting in the exemplary embodiment illustrated. For this purpose, a nickel-based alloy is used in the exemplary embodiment shown. Alternatively, in further exemplary embodiments, which are not specifically illustrated, the gearwheel core 50 can be produced by means of forming, for example of case-hardened steel, or by means of subtractive production, for example by machining a block composed of a nickel-based alloy. The gearwheel core 50 forms a first partial region of the gearwheel 10, which is formed with a first material, a nickel-based alloy in the illustrated exemplary embodiment.

[0035] Teeth 40 are integrally formed on the gearwheel core 50 by means of an additive production method, being applied by means of additive production in the exemplary embodiment shown. For this purpose, the teeth 40 are printed onto the gearwheel core 50 by means of laser deposition welding of the hard metal, tungsten carbide in the exemplary embodiment shown.

[0036] In the illustrated exemplary embodiment, the teeth 40 form an edge region, which is formed with a second material, here as described tungsten carbide.

[0037] According to the invention, the second material has a Vickers hardness which differs by more than 500 degrees of hardness from the Vickers hardness of the first material. In this case, the second material is also subject to internal compressive stresses on the first material, which makes the second material particularly robust with respect to mechanical stresses.

[0038] In further exemplary embodiments, which are not specifically illustrated, the second material can be printed on by means of laser wire deposition welding or thermal spraying or arc deposition welding or by means of a powder bed process, in particular laser beam melting and/or electron beam melting. In the illustrated exemplary embodiment, the Vickers hardness of the second material is more than 800 HV, and the Vickers hardness of the first material is less than 300 HV.

[0039] In further exemplary embodiments, which are not specifically illustrated, the teeth 40 as a whole do not form the edge region, but only a radially outer region of the teeth 40 forms the edge region. The inner part of the teeth 40 is part of the gearwheel core 50, on which the outer region is printed.

[0040] In further exemplary embodiments, which are not specifically illustrated, not only two materials with Vickers hardnesses that differ from one another are used, but three or more materials are used whose differing Vickers hardnesses increase in the direction of the toothed edge 100 of the gearwheel 10, i.e. in the radial direction R.

[0041] For this purpose, it is possible, for example, to use a nickel-based alloy whose alloy components are modified in certain regions in such a way that the Vickers hardness of the respective regions increases with increasing proximity to the toothed edge of the gearwheel 10, that is to say in the radial direction R.

[0042] In further exemplary embodiments, the edge region is not formed, or is formed not only with or on teeth 40 arranged on the outer circumference, but with or on teeth arranged on the inner circumference. Instead of a gearwheel 10, a rack can be provided as a transmission element according to the invention in further exemplary embodiments which are not illustrated separately, the edge region being formed with or on a toothed edge of the rack.

[0043] It is self-evident that, in the abovementioned embodiments, the edge region need not necessarily be formed on or with all the teeth 40. On the contrary, the edge region can also be formed, for example, on or with every second or third or nth tooth 40.