Rotary selector switch with illuminated symbols on outer ring and knob - uses single light source transmitting through ring of optically conductive material

摘要

A rotary switch has a central knob (4) with a finger grip (5) section that carries an illuminated symbol. The central section is surrounded by a fixed ring (3) with an insert region (29) carrying symbols that are illuminated dependent upon the selected position of the switch. A single light source (13) is used to provide the illumination for both the fixed symbols and the one on the knob. Inner (10) and outer (15) rings of optical material transmit the light from the source to the appropriate points. ADVANTAGE - Ensures even illumination for all symbols despite variation in form and surface.