See the following works of Pauls Mair:
http://mdz10.bib-bvb.de/~db/bsb00006570/images/index.html?id=00006570&fip=65.197.90.162&no=6&seite=49
These swords are called Fecht- or Schwertfeder. As far as I know, their were former made by used swords with grinded edges. In later days their made ...
