Traffic signal with time duration indicator and mechanical synchronization

Claim 1

A traffic signal comprising: a housing having a plurality of side walls, with each side wall including a first colored portion operatively related to a first lamp for transmitting the color of said first portion; and a second colored portion operatively related to a second lamp for transmitting the color of said second portion; a plurality of substantially semi-circular masks wherein each of said masks lies in a plane parallel to its respective said wall and rotating in that plane for sequentially covering and uncovering sections of said first and second portions; timing means including a single ring gear disposed within said housing and rotating therein for providing a synchronized mechanical linkage between said masks, wherein each of said masks includes a shaft fixedly attached thereto for causing rotation of said masks with each shaft including a driving gear fixedly attached to the shaft and operatively engaged with said ring gear, one of said shafts including drive means operatively engaged with a motor for causing rotation of said shaft and said ring gear; further wherein said first colored portion of each side wall includes an extension which is disposed laterally of said side wall and said second colored portion includes an extension which is disposed laterally of said side wall and vertically spaced from the extension of said first colored portion, said extensions comprising the sections which are covered and uncovered by said mask; a "LEFT TURN ONLY" signal means included in each of said side walls; a "STOP" signal means included in each of said side walls, switch means for selectively energizing either said first and second lamps or said "STOP" signal means, said switch means comprising a cam carried by said ring gear, a two position switch mounted stationarily with respect to said ring gear, and a switch actuator means for moving said switch between said two positions upon contact by said cam.