Rotary switch assembly having fixed contacts which may be selectively segmented

A rotary switch of the sliding contact type comprising

• a base plate of insulating material,
• a plurality of concentric, arcuate rows of stationary contact plates secured at a surface of said base plate,
• a rotary contact arm having a plurality of contacts, said rotary contact arm including a hub,
• said hub including an axially projecting portion being threaded at the outer periphery thereof, and said hub having a rectangular bore extending therethrough, said hub projecting portion being formed with two intersecting grooves perpendicular to the sides of said rectangular bore, said two intersecting grooves extending through said projecting portion,
• a rotatable shaft received in said hub, said rotatable shaft including a distal end portion having a rectangular cross-section, said distal end portion being inserted into said rectangular bore of said hub,
• a tapered nut having a central rectangular bore, said tapered nut threadedly engaging the threaded outer periphery of said projecting portion of said hub, such that the inner faces of said rectangular bore of said projecting portion of said hub forcibly presses against said distal end portion, thereby firmly securing said rotatable shaft to said hub, and
• a cover plate connected to said base plate for providing a cavity enclosing said rotary contact arm so that said contacts of said rotary contact arm slidably contact said stationary contact plates at positions corresponding to predetermined angles of rotation of said rotatable shaft.