I'm interested in the electronic levels mentioned in the thread "Surface plate maintenance (19 March 2009 et seq), specifically the Talyval from Taylor Hobson. This is the Mahr unit. I've been trying to find the original patents (long expired), but have struck out, probably because the US Patent Office only has searchable text back to 1976. I think it was Jon Elson who mentioned these patents.
What I have found is US Patents 4,023,413 and 5,022,264 from Wyler AG is Switzerland, a competitor. This is capacitive, not inductive like the Talyval unit.
Anyway, does anyone know the patent numbers, or the inventors name? Or an article or book reference? I have found only a number of truncated references or descriptions, but nothing with real meat on it.
Thanks,
Joe Gwinn