IC16 - RoTraCut

Non-Circular-Rotary-Turning of rotor shafts for electric traction drives

A secure connection between the rotor shaft and the laminated core is required for efficient electric motors with a long life. Currently, these shaft-hub connections are predominantly designed as cylindrical fits. This hinders a magnetically optimal design of the laminated core and causes high mechanical stresses in it, which can reduce its life. The friction-locked shaft-hub connection thus opposes the optimization of the overall rotor system.

A design of the connection rotor shaft - laminated core as a pretensioned positive-locking shaft-hub connection with an innovative, non-circular cross section of the rotor shaft has high potential in this respect. However, it has not yet been used due to a lack of economical manufacturing technologies.

Aim and approach

The aim of the project is to further develop the new and innovative process of Non-Circular-Rotary-Turning (NCRT) in order to qualify it for the highly productive and economical manufacture of new types of rotor shafts with non-circular cross-sections.

The main focus is on the identification and description of the geometric and process-side degrees of freedom of the synchronized-cyclic machining process in order to be able to use this knowledge in the sense of the product production codesign already during the product development.

In a first step, the geometric representability and locally effective process parameters are simulatively investigated, taking into account adjustments of the process parameters, the kinematics and the process strategy. The possibilities for process correction and individualization of the component cross-section with a given tool are also considered.
With the aim of validating the simulation and determining result variables, simulatively selected cross sections and processes are examined in experiments in a second step.
Finally, the findings are processed in the form of practical recommendations for action and transferred into a comprehensive technical description in order to ensure successful transfer to industrial application.