Cuckoo clock
It is unclear who built the first cuckoo clock. Different versions can be found in the literature.
- In 1615 Salomon de Claus had described how one can imitate the cuckoo call with two pipes.
- In 1619, Elector Johann Georg I of Saxony acquired a clock with a cuckoo scream.
- After that one occasionally finds the imitation of a cuckoo in music and figure machines until
- in 1669 Domenico Martinelli from Luca in Italy suggested using the cuckoo call to display the hours.
- Franz Anton Ketterer (1676 - 1749) from Schönwald is considered the first clockmaker to produce cuckoo clocks in the Black Forest.
Function
Until well into the 20th century, the striking mechanism was usually controlled by a lock disc. Today it is common for the step wheel and the release lever to interact. While the weight on the clockwork chain hoist is constantly moving downwards, the triggering of the strike is blocked. A step wheel with twelve steps is coupled to the hour hand. If the minute hand is in the "twelve o'clock position", a lock is released for a brief moment and a vertically toothed trigger lever (rake) falls onto the step wheel, thus differently depending on the time. At twelve o'clock the level is smallest and the trigger drops the lowest. The blockage is released and the chain hoist starts moving. It drives a cam wheel, which takes over the "operation" of the striking mechanism. Two bellows weighted with small weights or wooden blocks are lifted and released again with a time delay using a wire rod. Each bellows pumps air into a small pipe, creating the cuckoo tone (first the high tone, then the lower one). The impression of a cuckoo call only comes about when the sounding of the whistle is at the correct distance from one another. (see video on the next page)
In September 1850 Robert Gerwig, the director of the Grand Ducal Badische Uhrmacherschule in Furtwangen, called for a competition for a contemporary watch design. The most momentous design comes from Friedrich Eisenlohr, the architect responsible for most of the buildings along the Baden state railway. Eisenlohr provided the facade of a station house with a clock face. As an example you can see a rather rare table cuckoo clock from the end of the 19th century:
Movement: Cut-out brass movement with Black Forest hook walk. Hour and half hour strike on gong with simultaneous cuckoo call. Spring winding. Striking mechanism with worm and steel cable.
Housing: Brown colored wooden housing. Carved grapevines are placed on both front sides. Crowning of the roof with a carved cuckoo and vine leaves. Dial with Roman hours made of bone.
Pointer: Black Forest leg pointer.
Cuckoo clock
The eight-day cuckoo clock from the middle of the 19th century has a decorative, hand-carved case in the shape of a train station, which was only recently developed.
The bit on top is missing. On the right and left under a leaf (probably a vine leaf) there is a cuckoo sitting on a leaf. Below there are another six finely carved large leaves. The ivory hands are hand-carved, the dial has Roman numerals, the door for the cuckoo opens above the twelve, the pine-cone-shaped weights are gold-plated.