 The original invention goes back to the "Rollwagen" of the Schweizer Maschinenfabrik Winterthur (Swiss Locomotive and Machine Works, Winterthur) or SLM patented in 1880.It is a simple system for light loads that found applications even when the superior "Langbein" system was invented in 1881 by the Maschinenfabrik Esslingen (Esslingen Engineering Works) named after Paul Langbein being the director of the facilities in Saronno, Italy.The "Langbein" System uses claw pairs to form a yoke around the axles of the standard gauge bogies.