The cuckoo clock is traditionally mainly made in the Black Forest and is known worldwide. It is often a wall clock whose mechanical pendulum mechanism is equipped with a chain hoist and striking mechanism. Since the middle of the 19th century, the basic shape of the housing has mostly been modeled on a trainman's house with a sloping roof and decorated with more or less elaborately carved wooden ornaments. The real eponymous feature of the cuckoo clock, however, is the striking mechanism. A mechanical cuckoo serves as the acoustic time signal, which is movably mounted in the housing behind a door-like flap above the dial and is usually swiveled out every full hour. In addition, one or more cuckoo calls are heard every full hour depending on the number of hours (full hours are counted), usually together with a gong.
The “cuckoo call” is traditionally generated by a pair of organ pipes of different heights inside the clock. However, some patents manage with just one flute. Depending on the version, the mechanical cuckoo - traditionally carved from wood and painted, today often made from plastic - is moved or opens its beak to match the cuckoo call. In addition, other movable decorative elements can be attached to the outside of the clock, which move (usually only on the hour) (dancers, other birds). Today, in addition to the traditional mechanical cuckoo clocks, electro-mechanical models are also offered with quartz clockwork, electronically generated cuckoo calls, as well as chain hoist and pendulum fakes.