The importance of time to human beings is self-evident. In this way, it is also worth exploring how to time out. The ancients started their study of timing tools very early. The ancient kingdom of Billund invented the earth and the principle we all knew was to judge the time according to the change in the length and orientation of the sun. Ancient Chinese people also have similar inventions: sundial, clepsydra, hourglass, etc., leakage pot, hourglass is the use of water and sand flow meter time. Although these people can make a general understanding of the time, but there are still disadvantages: not accurate enough! If you want to know exactly what time it is in the end, is impossible to do.
The emergence of watches and clocks to solve this problem, watches and clocks, including two types of watches, which is measuring, indicating time precision instruments. Thanks to them, people can count time conveniently and accurately. What is the earliest mechanical watch?
The earliest mechanical clock is invented by the Eastern Han Zhang Heng - leaking turn armillary sphere, the gear will be muddy and time hitch together to make. Hourglass leaking impetus to the uniform rotation, transfer is a day. Only when the Northern Song Dynasty was in the Northern Song Dynasty was the great leader of the water transport system created by the prime ministers Su Song and Han Gong Lian, there was another little device called the escapement, known as the "heart" of the mechanical clock and watch.
Eastern Han Zhang Heng invented the leaking transparant instrument
The ancient mechanical clock in Europe, appearing in the 14th century in Europe, was driven by a heavy hammer attached to one end of a rope and the other end of the rope was wound on a shaft. As the weight dropped, the shaft rotated accordingly, The clock driving the clock rotation.
In 1510, the German locksmith Peter Henrias first used steel clockwork to replace the heavy hammer, creating a small mechanical watch with a crown wheel escapement. However, the timing effect of this watch was not satisfactory: Too tight, the pointer will go too fast; if the winding too loose, the pointer will run slowly.
Fortunately, human beings are wise, this shortcoming has been quickly improved, the Czech Jacob Heck designed a cone-shaped turbine, coupled with a winding mechanism composed of the table winding mechanism, wound winding, Force acting on the top of the tapered turbine; relax the spring, weakened pull force, the force acting on the bottom of the turbine, the turbine shape just to compensate for changes in the role of the clockwork, so clockwork machinery can maintain uniform operation. Will not appear "different elastic winding lead to different clock speed" phenomenon.
Around 1582, Galileo invented the gravitational pendulum. In 1657, Huygens introduced the gravitational pendulum into the mechanical clock and produced the world's first precise pendulum clock, a major event in the history of mechanical clocks.
Compared with the previous need to drive the mechanism to promote the symmetrical horizontal wall clock, pendulum clock apparently to save a lot more, using the earth's gravity to promote. Later, the pendulum was applied to the clock, clock accuracy is also due to higher and higher. By the middle of the 17th century, the clock's error was only 10 minutes a day.
Modern Western mechanical watches were introduced to China in the late Ming Dynasty. In 1601, Italian missionary Ricci donated two self-explanatory bells to the Ming Dynasty Wanli emperor. It is these two bells that have had an impact on the manufacture of the mechanical clock in our country. It is said that at that time, Matteo Ricci had also renovated it. In order to adapt it to China's timekeeping habits, the 24-hour clock was changed to 12 o'clock, Changed into Chinese numbers, and divided the day into one hundred minutes, dividing each paragraph into one hundredth.
In 1660, Hook invented the hairspring, used to control the reciprocation of the balance wheel in isochronism, the emergence of flexible elements in the clock so that the clock toward a more sophisticated direction.
Although there are many mechanical clock structure, but the working principle is much the same. It is composed of the original motive force, transmission, escapement speed governor and pointer lines on the dial-needle lines and so on. In the 18-19 century, the clock and watch manufacturing industry has gradually realized the industrialization of production. In the 20th century, the rapid development of the electronics industry gave birth to the development of mechanical clocks, battery-driven clocks, electro-mechanical watches, digital quartz clocks, etc. Come out one by one. In 1969, there was a quartz watch, quartz watch timing quite accurate error of 0.0001 seconds per day or less.
Mechanical clock history has also appeared a lot of interesting tidbits, sailing clock is one of them. Navigation clock, as its name implies, is a precision clock for ocean navigation. Nautical clock, invented in the second half of the 17th century, when the ship sailing no technical means to measure the longitude, the use of navigation clock records the time of the first meridian, and then the location of the vessel noon time comparison, through the difference between the conversion Longitude of the location.
In order to compete for maritime hegemony, all European countries have invested their money in finding ways to measure longitude. Britain, of course, is the most active one and has introduced a bill that claims that as long as anyone can find a way to measure longitude at sea, it will get 20,000 pounds. There must be brave husband under the big money, John Harrison, the self-taught clock maker tangled to receive this award.
This is a very long campaign to pull Harrison in the sketches get Observatory director Harley, who is the discovery of Halley's comet that recognition, they began to make. After five years, Harrison produced the first sailing clock, let's call it H1, weighed 34 kg. Harrison conducted the test and found it to be far more accurate than all the measurements of the time, but he was not content with it and made subsequent improvements on that basis, H2, H3, but this monster Not easy to carry, Harrison is also big. Occasionally, he discovered and used small high-frequency vibrators, although already 60-year-old, Harrison throw do not mind to come back, after the great design theory produced H4 is only a little larger than the pocket watch, however, This is 6 years later.
The award-winning board commissioned Harrison's son to take the H4 to expedition to Jamaica and 81 days of maritime voyages found that the H4 was only five seconds slower, with errors well below the maximum set by the commission.
In the "war of longitude", the United Kingdom won the first chance to lay the foundation for maritime hegemony and lay the dominant position in the world. From this it can be seen that it is of great significance to obtain accurate time. Navigational positioning is no longer a distant dream. Watches also enter the new era of quartzization, which combines microelectronics and precision machinery. Getting accurate time and location is a simple matter. Have to admit that the development of science and technology has brought us great convenience.
This article is reproduced, does not represent the world position of million table.
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