The development of traffic lights
According to the data, during the Kuomintang rule, there were 50 traffic command posts in Shenyang City, of which there was no traffic light, and 19 traffic lights (4 automatic signal lights, 15 manual light lights) and no lights were repaired and added. 15 booths. By the early 1960s, the city had reached 30 signal lights. In the early 1990s, Shenyang completed the construction of the first-loop traffic signal automatic control system and closed-circuit television monitoring system, speeding up the intelligent traffic process. Shenyang traffic lights develop and improve, reflecting the evolution of traffic lights.
The industrial revolution that originated in the central England in the 18th century affected the entire continent of Europe and led to the industrial revolution in many countries at that time. In terms of production technology, the industrial revolution replaced the manual factory with a machine factory, creating enormous productivity, and human beings entered the steam era, and the UK became a "world factory."
With the rumbling of the steam locomotive, the railway traffic signal came into being. Since the train was operated in a single train according to the fixed timetable, and the train was stopped, it was not very easy. Therefore, the signal used on the railway had only one command: pass. . At that time, the land transport vehicles in the United Kingdom were mainly carriages. Some people transplanted the train lights to the carriage carriage. In 1858, the main street of London, England, installed red and blue mechanical wrench-type signal lights with gas as the light source. Commanding the carriage, this is the world's first traffic light.
In 1868, the British mechanical engineer Nayt applied it to road traffic. On the cast iron columns at the intersection of George Street and Hillic Street near the London Parliament Building, a red and green rotating square glass lantern appeared. Gas-fueled traffic lights. This type of traffic signal is manually manipulated to change color, red means "stop", green means "attention", mainly for the convenience of members of the House of Representatives to work safely. Unexpectedly, an accident occurred during the use, causing a police officer who was on duty to die on the spot. No one dared to use this traffic light.
Until the end of the 19th century, Edison invented the electric light, providing a prerequisite for the birth of electric energy-based traffic lights. In 1914, the city of Cleveland in the United States took the lead in recovering the traffic lights, but at this time it was already an "electrical signal light." Later, cities such as New York and Chicago re-emerged as traffic lights. The signal consists of red, green, and yellow circular light projectors mounted on a tower in Fifth Avenue, New York City. A red light indicates a stop, and a green light indicates a pass. Later, controlled traffic lights and infrared lights appeared.
In 1918, the Detroit traffic policeman William Potts invented the world's first artificially-operated electrical lighting "red, green, yellow" three-color traffic lights. The traffic signal is installed on the signal tower at the center of the intersection, and the circular emitters of red, green and yellow are installed on the four sides of the signal tower. The yellow light signal indicates passage, the red light signal indicates stop, and the green light signal indicates that it can turn left and right.
With the development of automobiles, people realize that a car is a high-speed vehicle. If a green light is directly converted into a red light while driving, the passenger is easily injured by the sudden braking of the car. This three-color signal tower appeared on the street and was immediately welcomed. It was adopted by Japan two years later and adopted by the United Kingdom seven years later. The United Kingdom has three colour lights: the green light means traffic, the red light means no traffic, and the yellow light indicates warning. Traffic lights have also become an important part of our transportation composition. From a young teacher, we must educate us to stop at a red light, green light, yellow light, and follow the orderly rules. Urban traffic can leave the traffic lights without a moment. Even in the dead of night, the traffic lights still work as usual.