| 主权项 |
1. A switch assembly for controlling an electrical device, the switch assembly comprising:
a circuit board; a light source mounted on the circuit board; a pair of electrical contacts on the circuit board; a thumbwheel knob rotatably mounted on the circuit board, the thumbwheel knob being configured to be rotated about an axis substantially parallel to the circuit board; a transparent window formed on the thumbwheel knob on which a symbol is applied or formed, the transparent window extending through an opening in the thumbwheel knob, the symbol being selected from the group consisting essentially of a word, letters, numbers, or a graphic; a light guide positioned within the thumbwheel knob for directing light from the light source to the transparent window to illuminate the symbol, the light guide comprising:
a plurality of angled surfaces; anda central aperture, the plurality of angled surfaces being configured to reflect light from the light source to the central aperture and the central aperture being configured to reflect light from the angled surfaces to the transparent window; a detent mechanism for providing tactile feedback when the thumbwheel knob is rotated; an electrical conductor configured to contact and move relative to the contacts; and a rack and pinion assembly for moving the conductor relative to the contacts when the thumbwheel knob is rotated, the rack and pinion assembly comprising:
a rack coupled with the electrical conductor; anda pinion coupled with the light guide and operable to move the rack and the electrical conductor when the thumbwheel knob is rotated. |
