I happened by this broken single weight Cuckoo clock that had most of its pieces in a bag at a resale store. The clock was made in Western Germany with a Helmut Kammerer movement probably by the Hekas Company. The cuckoo chirps its two-tone sound once every 15 minutes. No gong or door opening action on this bottom of the line model, but it does have a bird that moves.
The original bellows had deteriorated and fallen off and the clock was missing a minute hand and the pendulum.
The movement has a 4-lobed cam that rotates once an hour and keeps resetting the bellows.
The action is all specially bent wires after that.
Hopefully it will work again…