The number clock is a clock that displays the time in a number (that is, the number or other symbols), which is the contrary to the analog clock.

Digital clocks are usually associated with electron -driven, but the number description only refers to display, not the driving mechanism. (Simulation and digital clocks can be driven by mechanical or electronic, but the clockwork mechanisms with digital display are rare).

XXX digital pocket watch is the invention of Austrian engineer Josef Pallweber. He invented the jumping device in 1883. The device is not a traditional dial, but there are two windows on the enamel dial. Through they, they can see the CD -ROM rotating disc. Keep the tradition of seconds. By 1885, the Pallweber mechanism of Cortébert and IWC had been listed in the pocket watch; it can be said that the future rise and business success of the Kingdom of IWC has contributed. The principle of Polberry jumping movement has appeared in the watch as early as the 1920s, and is still using it. Although the initial inventor did not have a watch brand at the time, his name was later resurrected by a newly established watch manufacturer.

The Plato clock uses similar ideas, but the layout is different. These springs are composed of a glass cylinder with cylindrical cylindrical inside, and small digital cards with numbers printed on the cylindrical body are flipped over time. These cards will flip. Plato bell was launched at the St. Louis World Expo in 1904, produced by Ansonia Clock Company. EUGENE FITCH in New York obtained the clock design patent before 1903.13, and Josef Pallweber used a digital card (different from his patent with mobile disk in 1885) in Germany (DRP No. 54093). The German factory AKTINGESELLLLSCHAFT Für Uhrenfabrikation Lenzkirch made such a digital clock in 1893 and 1894.

The earliest digital alarm patent was D.E Protzmann and others registered in the United States on October 23, 1956. Protzmann and his colleagues also applied for a patent for another digital clock in 1970. It is said that the clock used the least activity parts. Two side boards are placed between them, while the external motor and cam device control movement.