Hello Arnold,
I did some research on "Saalfrank and Tange". The company was probably an armature winding factory that mainly produced electric motors.The company was located at Schmiedestraße 31, in Kappeln an der Schlei, Schleswig-Holstein, Germany.
Under the link you will find a reference to the company.
https://www.schulzeitreisen.de/?p=28516
However, you may already be familiar with it.
Hello Jürgen - thank you for the informations about Saalfrank & Tange. I do have also an article from a
Tintoy Magazin 02/1997 about the magnetic motors - unfortunately only in German. The "Steyr" from DDR was
a very similar one - but horizontal. Greetings, Arnold