Development of an ultra-efficient lightweight gearing stage with internal cooling
Duration: 01.07.2019 - 30.06.2021
The aim of this project is the prototypical development of an innovative and functionally integrated gear stage for next generation electric vehicles using LBM or FDM production. The focus is on the aspect of reducing environmental pollution. Important criteria of this new holistic approach are the oil-free and thus almost maintenance-free operation, the range increase through extreme lightweight construction as well as the damping in the sound transmission starting from the tooth mesh due to an optimal wheel body geometry design with labyrinth structures.
To work on the project, a close connection of competences in the areas of additive-generative manufacturing and transmission technology (Fraunhofer IWU), coating competence (Fraunhofer IWS) as well as FDM manufacturing of reinforced plastic wheel body structures (3DPrintpetrol) and gear finishing (Chemnitzer Zahnradfabrik) is required.
Classification in the AGENT-3D landscape
The planned CoolGear technology project addresses a fundamental key factor for the successful industrial application of additive-generative drive train components. The innovative core consists of extending components by areas that cannot be produced by milling and casting, e.g. complex structures, contour-following fluid-carrying elements by means of additive-generative manufacturing, thus creating significant added value compared to the state of the art. In this way, the very high component complexity and integration of additional functions of additive-generatively manufactured components is to be combined in an economically sensible way with gear grinding and final coating for maximum efficiency in dry running. At the same time, the balancing act between necessary strength, labyrinth structure for acoustic damping (structure-borne sound transfer path starting from the tooth mesh to the hub) and lightweight construction can be ideally implemented in the wheel body without significant manufacturing restrictions. The essential research and market goals of the AGENT-3D consortium, which consist in the achievement of industrial application maturity of additive-generative manufacturing processes and their sustainable economically successful market implementation, are thus directly supported.
Procedure and technical target definition
The main goal of the project is the prototypical implementation of a fully operational first gear stage of an e-transmission, which is evaluated in advance according to vehicle validation regulations.
The final gearing stage differs from the state of research in the following points:
• lubricant-free operation
• optimized force flow-adapted 3D print structures for maximum lightweight construction
• Reduced noise emission inside and outside the e-vehicles (wheel body acoustics, special gearing)
• innovative and resource-efficient manufacturing processes: efficient use of materials on lightweight wheel bodies and stub shafts
The following are to be listed as the technical target parameters of the final revised, additive manufactured and coated variant:
• Reduction of the sound radiation/ structure-borne noise input by at least 3 dB
• Weight reduction of the gear stage incl. oil quantity by 25
• Deviation in efficiency and strength of less than 5 % in comparison to oil-lubricated series production despite oil-free tooth engagement
In the context of dwindling resources and growing awareness of climate protection, electric mobility is becoming increasingly important. A significant breakthrough of electric mobility is expected between 2020 and 2030.
The aim of the project is the prototypical development of an innovative and functionally integrated gear stage for next generation electric vehicles, manufactured by means of LBM or FDM processes. The focus is on the aspect of reducing environmental pollution. Important criteria of this new holistic approach are the oil-free and thus almost maintenance-free operation, the range increase through extreme lightweight construction as well as the damping in the sound transmission starting from the tooth mesh due to an optimal wheel body geometry design with labyrinth structures.
In combination, this project will thus make a significant contribution to the fulfilment of the strategic goal of the overall AGENT 3D project, namely additive-generative manufacturing processes for broad industrial application, especially against the background of new and innovative electric drives. Interdisciplinary links with other technology projects will be established.