History of clock development

Clock is one of the earliest objects invented by human beings, because it is necessary to measure the time interval continuously. Some natural time intervals (such as day, leap month and year) can be obtained by observation, and shorter time intervals need to use clocks.

For thousands of years, the principle of timing equipment has also changed greatly. A sundial is the change of time by the shadow of an object on a plane. There are many instruments to calculate the time interval, including the most widely known hourglass. The water clock matched with the sundial may be the earliest timing instrument.

Europe invented the escapement in 1300, and later created the first mechanical clock, which can use oscillating timing equipment such as balance wheels. Clockwork-driven clocks appeared in15th century, and the clock industry began to develop in15th century to16th century. The pendulum clock was invented in 1656.

Therefore, the accuracy of timing is further improved. At that time, navigation required the accuracy of time, which also promoted the reliability and accuracy of clocks and watches. The electronic clock was patented in 1840, and the development of electronics in the 20th century produced a clock with no mechanical movement at all.

At present, the timing element in a clock is a harmonic oscillator, an object that oscillates at a fixed precise frequency. The harmonic oscillator can be a simple pendulum, a tuning fork, a crystal or an electron oscillation when an atom emits microwave.

Analog clocks use hands and angles to represent time, while digital clocks use numbers to represent time. There are two kinds of time expressions: twelve-hour system and twenty-four-hour system.

Most digital clocks use electronic equipment, liquid crystal, LED and vacuum fluorescent display to display the time. Clock function is also one of the standard functions of computers and mobile phones.

For convenience, distance, telephone or the needs of the blind, an auditory clock is used to tell the time by sound. In order to meet the needs of the blind, there are also clocks for the blind that can sense their own time by touching, some of which are similar to the traditional time, but by adjusting their design, they can directly touch the surface to know the time without affecting the timing function. Timing technology is also constantly developing.

Extended data:

Primitive people judged time according to the change of sky color and the brightness of the sun. Ancient Egypt discovered that the shadow length would change with time and invented the sundial to measure time in the morning. They also found that the time needed for water to flow was fixed, so they invented the water clock. In ancient China, people also had a tool to time with water-dripping water from a copper pot.

China not only used water to time, but also ancient China folks used burning incense to time. Dragon boat time is more fragrant, and it is an instrument for timing by burning incense. It also has the function of ringing the bell regularly.

On the dragon boat, there are several small strings with metal balls tied at both ends, and incense is burned under the strings. Every once in a while, incense will burn a thread, and when the metal ball falls into the container below, it will ring a bell. This kind of incense burning timepiece was first seen in the literature of Song Dynasty.

It is not accurate to calculate the time with incense, but it used to be very popular because it is simple and easy to use, and it is very suitable for folk use. According to the literature, some of them are fragrant and can be burned for a day and a night, and some can even be burned for a month.

In A.D. 1088, Su Song and Han Gonglian, scientists of the Song Dynasty, made the first aquatic instrument stage in history, which was composed of an armillary sphere, an elephant and a mechanical timer.

It is driven by hydraulic power and has a scientific escapement mechanism. About 12 meters high and 7 meters square. It is divided into three layers: the upper layer is equipped with an armillary sphere for astronomical observation; The middle layer can simulate celestial bodies for synchronous demonstration; The lower layer is the heart of the instrument, and the formation and output of timing, time telling, power supply are all on this layer.

In A.D. 1276, Guo Shoujing of China Yuan Dynasty made a big leaky lamp. It is driven by water power, which drives the puppet to automatically say the time of "ring the bell for a while, carving the drum for two minutes, ringing the cymbals three times and ringing the cymbals four times" through a gear train and a rather complicated cam structure.

Since the Song Dynasty, the 24-hour clock system started at 12, and one minute is today's 15 minutes, which is more than 300 years earlier than the German desk clock.

In A.D. 1283, the first mechanical clock driven by heavy objects appeared in English monasteries.

In13rd century, monks in northern Italy began to build bell towers to remind people of the time of prayer.

In A.D. 1360, Zhan Xiyuan created the "five-wheel hourglass", which consists of gears and a time disk.

/kloc-in the middle of the 0/6th century, Germany began to have clocks on the table. Those clocks have only one hand, and the clock face is divided into four parts, so that the time is accurate to the nearest fifteen minutes.

In A.D. 1657, Huygens discovered that the frequency of pendulum can calculate time, and made the first pendulum clock. 1670, an Englishman William Clement invented the anchor escapement.

In A.D. 1797, Eli Terry, an American, obtained the patent right of clocks and watches. He is regarded as the originator of American watch industry.

1840, the British watchmaker Alexander Bain invented the electric clock.

In A.D. 1946, American physicist Dr. isidore Rabbi figured out the principle of atomic clock. Two years later, the world's first atomic clock was made, and it is still the most advanced clock. Its operation is completed by the natural vibration of cesium atoms and hydrogen atoms, and it can run accurately within 300 years with very small error.

From 18 to 19 century, the watch manufacturing industry gradually implemented industrial production.

In the 20th century, it began to enter a timely period.

2 1 century, the technology of radio-wave clock with automatic time adjustment developed according to the principle of atomic clock gradually matured.

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