| 摘要 |
PROBLEM TO BE SOLVED: To enable to guide light from a light source arranged in the vicinity of an opening of a cylindrical base part toward an outer periphery edge side of a knob cap without being shielded by an inner periphery face of the cylindrical part, in case an operation panel downsized as an outer diameter of the dial knob is kept as before in switch mechanisms.SOLUTION: Switch mechanisms 2, 3, 4 each contain a light guide member 43 in an inner space 42 zoned by the cylindrical base part 11 and the dial knob 15, and the light guide member 43 is structured of a light-receiving face 44 facing a chip LED 40 of a circuit board 21 for light of the chip LED 40 to be incident into, a light-outgoing face 45 emitting light toward a knob cap 16, a light-propagating part 46 propagating light received at the light-receiving face 44 toward the light-outgoing face 45, and a light-diffusing part 47 for diffusing the light propagated from the light-receiving face 44 to the light-propagating part 46 up to the outer periphery edge side of the light-outgoing face 45. Light is surely made to reach the outer periphery edge of the light-outgoing face 45, even if a size of the light-receiving face 44 arranged facing the opening of the cylindrical base part 11 is smaller than that of the light-outgoing face 45 positioned inside the dial knob 15. |
