No abstract

Improving the efficiency in production is always the aim. In many applications, where progressive stamping approaches the technological limits, rotary cutting is successful. Relevant applications to name are the processing of paper, card boxes, packaging and simple perforated steel profiles. The main limiting factors of the stamping technology are the accelerations and decelerations in sheet feed and stamping motion. In contrast rotary cutting is a continuous process which leads to greater speeds and higher output. While performing the electrical steel strip between two cylindrical tools in stamp and die arrangement, the laminations are being cut out. Rotary cutting in the manufacture of laminations is a great challenge and a research topic at the Bavarian Technology Center for Electric Drives at the FAU. This paper provides the main technological differences between progressive stamping and rotary cutting regarding the process structure. Furthermore the geometric and technical parameters of the rotary cutting process are described mathematically. Finally the correlation of process parameters are identified.

The workflow for processing laminations is such an innovating field. Every piece of the lamination stack for rotor and stator is cut at least one or several times. For this complex aim, mechanical cutting press systems with eccentric drives are widely used. This paper presents a new approach towards continuous rotational cutting compared to traditional press systems with vertical tools. This approach has advantages towards machine masses, production speed, tool flexibility and new materials. A machine prototype is presented and a production benchmark between these two technologies is given.