I've added some more topics. I don't know if they're the broadest and most important, though. In many cases, I'm sure they're not, but I don't know which ones would be so considered. Please, please check and edit the entries in your areas of expertise. See talk:Wikipedia arranged by topic.
... extent by the slipping friction.
The device is covered by US patents 3,726,146 (1973) and 5,353,655 (1994) by L.A. Mishler and US patent 5,800,311 (1998) by ...