Electric or electronic proximity switch

摘要

The proximity switch comprises a sleeve-shaped metal casing (1) which has been made by die casting of Zn, Al, Mg, Cu, Pb, and/or Sn alloy. The casing may have a smooth or threaded surface. The casing outer surface may contain a thread-free section (2) and a section (3) locating an external thread. The thread-free section typically has a smaller outer dia. than that contg. the external thread. The latter may have flat, thread-free sections on opposite sides. The thread-free section may have an aperture for exposing the switching state to visual inspection.