This is an example of a component in a single-choke carburetor. It is an automatic choke, which can be heated either electrically, or through the coolant. It was responsible for closing the choke-flap during cold starting.The air supply was thereby reduced, and through the increasing vacuum, the fuel amount was raised.
With the increasing warmth of the engine, the choke-flap is automatically opened again. This occurs through a bi-metal spring, around whose two connections on the left, the coolant flows. At the same time, through the electric heating, a time-dependent controller is reached. A bi-metal spring by the way, consists of two metals, which when heated, expand differently from each other, thereby decreasing the spring tension. 04/10