At the beginning of the 19th century, in York City in Central England, red and green clothes represented different identities of women. Among them, the woman in red means I am married, while the woman in green is unmarried. Later, carriage accidents often happened in front of the parliament building in London, England, so people were inspired by the red and green clothes. On December 10, 1868, the first member of the signal lamp family was born on the square of the parliament building in London. The lamp post designed and manufactured by the British mechanic de Hart at that time was 7 meters high, and hung with a red and Green Lantern – gas traffic light, which was the first signal light on the city street.
At the foot of the lamp, a policeman with a long pole pulled the belt to change the color of the lantern at will. Later, a gas lampshade was installed in the center of the signal lamp, and there were two pieces of red and green glass in front of it. Unfortunately, the gas lamp, which was only available for 23 days, suddenly exploded and went out, killing a policeman on duty.
Since then, the city’s traffic lights have been banned. It was not until 1914 that Cleveland in the United States took the lead in restoring traffic lights, but it was already an “electrical signal light”. Later, traffic lights reappeared in cities such as New York and Chicago.
With the development of various means of transportation and the needs of traffic command, the first true tricolor light (red, yellow and green signs) was born in 1918. It is a three color round four-sided projector, which is installed on a tower on Fifth Street in New York City. Because of its birth, the urban traffic has been greatly improved.
The inventor of the yellow signal lamp is Hu ruding of China. With the ambition of “saving the country through science”, he went to the United States for further study and worked as an employee of General Electric Company of the United States, where Edison, the great inventor, was the chairman. One day, he stood at a busy intersection waiting for the green light signal. When he saw the red light and was about to pass, a turning car passed with a whirring sound, which scared him in a cold sweat. When he returned to the dormitory, he thought over and over again, and finally thought of adding a yellow signal light between the red and green lights to remind people to pay attention to the danger. His suggestion was immediately affirmed by the parties concerned. Therefore, the red, yellow and green signal lights, as a complete command signal family, have spread all over the world in the field of land, sea and air transportation.
The earliest traffic lights in China appeared in the British concession in Shanghai in 1928. From the earliest hand-held belt to the electrical control in the 1950s, from the use of computer control to modern electronic timing monitoring, traffic lights have been constantly updated, developed and improved in science and automation.
Post time: Jul-01-2022
