For what it's worth, I can add what I know about the company.
Scheidegger was a Swiss-German typing school that had several locations in Germany and throughout Europe (Austria, Belgium, England, France, Netherlands, Switzerland).
I believe that it was because of the company’s size, and its access to new typists, it logically branched out into selling private label typewriters. Some of these typewriters were identical to the manufacturer’s version of that model, but some were modified for Scheidegger specifically as machines designed to learn touch typing on. The Scheidegger Typomatic TMS branded Adler below is an example of one.
There were of course other typewriters available to learn touch typing; a number of different Olympia-Tip models immediately come to mind.
I don’t know how many different manufacturers produced Scheidegger-branded machines, but I have seen models made by Princess (Keller & Knappich), Adler (and Triumph), and Olivetti.
