Wagnerian hammer

Wagnerian hammer (also called rheotome) for the magnetic interruption of the circuit of a spark inductor from around 1900. The name comes from Johann Philipp Wagner, who invented it in 1836, and the form of contact he chose. A Wagnerian hammer consists of an armature moved by an electromagnet and a switching contact (normally closed contact). When it is switched on, a contact is closed and the current flowing in the coil of the electromagnet attracts the armature. The switching contact opens and interrupts the current. The magnetic field breaks down and the switching contact closes again. He is pulled by a return spring in its rest position. This process repeats periodically. It is a self-excited, feedback system.