The origin of the development of traffic lights

According to the data, during the Kuomintang rule, there were 50 traffic command posts in Shenyang, of which a certain proportion did not have traffic lights. Later, 19 traffic lights were repaired and added (4 automatic lights, 15 manual lights), no lights 15 sentry boxes. By the early 1960s, there were 30 signal light posts in the city. In the early 1990s, Shenyang completed the construction of the first ring road traffic signal automatic control system and closed-circuit television monitoring system, which accelerated the process of intelligent transportation. The development and perfection of traffic lights in Shenyang reflects the evolution of traffic lights. The Industrial Revolution, which originated in the central part of England in the 18th century, affected the entire European continent and led to industrial revolutions in many countries at that time. In terms of production technology, the Industrial Revolution allowed machine factories to replace manual workshops, creating huge productivity. Mankind entered the steam age and Britain became the “world factory”. With the rumbling of steam locomotives, railway traffic signals came into being. Because trains run in a single train according to a fixed timetable, and it is not easy for trains to stop, the signal used on railways has only one command: pass . At that time, British land transportation was mainly horse-drawn carriages. Some people transplanted train signal lights to direct carriage traffic. In 1858, red and blue mechanical wrench-type signal lights with gas-fired light sources were installed on the main streets of London, England. Direct the carriage of carriages through, this is the world's earliest traffic lights. In 1868, British mechanical engineer Nayt applied it to road traffic, so the red and green rotating square glass lanterns appeared on the cast iron pillars at the fork of George Street and Hirich Street near the Houses of Parliament in London, England. , Traffic lights using gas as fuel. This kind of traffic light is manually manipulated to change the color. Red means 'stop' and green means 'attentionUnexpectedly, an accident occurred during the use process, resulting in the death of a policeman on duty nearby. No one dared to use this kind of traffic light. It was not until the end of the 19th century that Edison invented the electric light, which provided a prerequisite for the birth of traffic lights that use electric energy as energy. In 1914, the city of Cleveland in the United States took the lead in restoring traffic lights, but at this time it was already an 'electrical signal light.' Later, traffic lights reappeared in cities such as New York and Chicago. This signal light is composed of red, green, and yellow circular projectors, installed on a high tower on Fifth Avenue in New York City. Red light means stop, green light means passage. Later, there were traffic lights and infrared lights with control. In 1918, Detroit traffic police William Potts invented the world's first manually operated electric lighting 'red, green, and yellow' three-color traffic signal light. This kind of traffic signal light is installed on the signal tower in the center of the intersection. The top four sides of the signal tower are equipped with red, green and yellow circular projectors. The yellow light signal means passage, the red light signal means stop, and the green light signal means you can turn left and right. With the development of automobiles, people have realized that automobiles are a high-speed means of transportation. If a green light is directly converted to a red light while the vehicle is driving, the passengers will easily fall due to the sudden braking of the vehicle. As soon as this three-color signal tower appeared on the street, it was immediately welcomed. It was adopted by Japan two years later and adopted by Britain seven years later. The United Kingdom has regulations on three-color signal lights: a green light means traffic, a red light means no traffic, and a yellow light means warning. Traffic lights have also become an important part of our traffic. From an early age, the teacher taught us to stop at a red light, run at a green light, and go slowly at a yellow light, and to pass in accordance with orderly rules. Urban traffic never leaves the traffic lights. Even in the dead of night, traffic lights still work as usual.