TRAFFIC SIGNAL CONTROL SYSTEM

• US 3,731,271 A
• Filed: 11/26/1971
• Issued: 05/01/1973
• Est. Priority Date: 11/26/1971
• Status: Expired due to Term

• Current Assignee: Akira Muramatu, Tadao Endo
• Original Assignee: Akira Muramatu, Tadao Endo
• Inventors: Muramatu, Akira, Endo, Tadao
• Primary Examiner(s): Claffy, Kathleen H.
• Assistant Examiner(s): Myers, Randall P.
• Application Number:
  US05/202,536
• Time in Patent Office: 522 Days
• Field of Search: 340/35,40,41,37
• US Class Current: 340/913
• CPC Class Codes: G08G 1/081 Plural intersections under common control

Abstract

A relatively wide area in which the traffic signals are to be controlled is divided into a plurality of local areas each having a local signal controller. There are provided a plurality of different cycle signals and a plurality of different synchronizing signals paired with the cycle signals. A master controller always watches the traffic condition in each of the local areas and causes each local controller to select that one of the pairs of cycle signals and synchronizing signals which is most suitable for control of the traffic signals in each local area under the present traffic conditions. In turn, each local controller uses the selected cycle and synchronizing signal to control a plurality of intersection controllers in the local area, each intersection controller being associated with an intersection traffic signal.

Claims

1. A system for controlling the traffic signals within a wide area divided into a plurality of local areas, comprising:

a master controller, a local controller provided for each said local area, said local controllers having respective addresses, said master controller including a first pulse register for calling one of said addresses;

means for providing a plurality of different cycle signals and a plurality of different synchronizing signals to each of said local controllers, each of said synchronizing signals paired with one of said cycle signals;

means included in each said local controller and operable in response to a command signal produced by said master controller to select one of said pairs of cycle signals and synchronizing signals;

said master controller including a second pulse register for storing said command signal;

means included in said local controller for obtaining from said selected cycle signal a plurality of cycle signals of different lengths; and

means for applying said command signal to that one of said local controllers whose address has been called, so that the traffic signals in each said local area are controlled by the selected cycle signal and synchronizing signal.

2. The system of claim 1, wherein each said local controller further includes means for obtaining from said selected cycle signal and synchronizing signal a plurality of synchronizing signals indicating the lapse of times of different lengths within one signal cycle.