From BC 140 to BC 100, the ancient Greeks made timepieces consisting of 30 to 70 gear systems for the Olympic Games. This instrument, named "Antichi Sila Instrument", consists of 29 interlocking copper gears and several dials, which is equivalent to the size of a lunch box.
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.
1946, American physicist Dr. Libby 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 ammonia atoms, and it can run accurately within 300 years with very small error.
Extended data:
Structure of the clock:
There are many structural forms of mechanical clocks and watches, but their working principles are basically the same. They are all composed of prime mover system, transmission system, escapement governor, pointer system and winding system.
Mechanical clocks and watches take clockwork as the power system, and drive the escape governor through a transmission system composed of a group of gears; Then the speed of the transmission system is controlled by the escape governor in turn; The transmission system drives the pointer mechanism while pushing the escapement mechanism, and the rotation speed of the transmission system is controlled by the escapement mechanism, so the pointer can indicate the time on the dial according to certain rules; The winding pointer system is a mechanism for winding springs or moving pointers.
In addition, there are some additional mechanisms that can increase the functions of clocks and watches, such as automatic winding mechanism, calendar (double calendar) mechanism, alarm device, moon phase indication and timing mechanism.
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