Attachment to traffic light apparatus for visual indication of traffic light duration

摘要

The device of the invention comprises an attachment to a conventional traffic light and is connected to its side wall for visually indicating the duration of the time remaining till switching of the current green, yellow, or red light in proportion to the dimension of the illuminated portion of the indicator. In accordance with one embodiment, the device is made in the form of a housing with a rotating drum which is divided into three sections by nontransparent partitions, each containing an individual lamp. The cylindrical surface which defines the periphery of each section of the drum has a transparent portion in the form of a wedge. When the drum rotates, the lit sector is shown in the window of the device so that during rotation of the drum, the dimensions of the lit portion of the drum shown through the window decrease proportionally to the remaining part of the current traffic light signal. Other embodiments have visual displays in the form of a plurality of gas-discharge lamps arranged side by side and switched on and off in a predetermine sequence, in the form of serpentine lamps of triangular configuration, in the form of vertical rectangular stripes of variable width, etc.