How to adjust the month of perpetual calendar?

Perpetual calendar refers to a watch that does not need to manually assign dates and months for ten thousand years.

The calendar design of general mechanical watches takes 3 1 day as a cycle. Therefore, in each abortion with only 30 days, the date number must be manually moved forward by one day. The perpetual calendar will automatically jump to 1 of next month according to whether the end of the month is 3 1 of the big month or 30/of the small month. A calendar with February 29th can be automatically adjusted every four years in a leap year, which is called a "big calendar", while a calendar that cannot be displayed as February 29th in a leap year and needs to be adjusted every four years is called a "small calendar".

Clock:

Clock is one of the earliest objects invented by human beings, because it needs to measure the time interval continuously. Some natural time intervals (such as days, leap months and years) can be obtained by observation, and shorter time intervals require the use of clocks. For thousands of years, the principle of timing equipment has also changed greatly. The sundial uses the change of the shadow of an object on the plane to calculate the time interval. There are many kinds of instruments that can 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 device in 1300, and later created the first mechanical clock, which can use oscillating timing equipment such as balance wheels. Clockwork-driven clocks appeared in the15th century, and the watch industry began to develop in the15th century to16th century. The pendulum clock was invented in 1656, so the accuracy of timing was 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.