Spark plugs: burnt by spark
While still working at the factory, I was arguing hoarsely with a colleague from the neighboring department, who carefully sawed the side electrode of the spark plug with a jigsaw to “get two sparks instead of one” every time.
The arguments did not work - moreover, when the “inventor” connected his creation to a pulse generator and an ignition coil, the spark doubled in front of everyone’s eyes, sparkling at both ends of the mutilated electrode.
The crowd ceased to applaud only after I lowered the frequency of the generator from 200 hertz to 1 - that's where everyone saw that the lone spark had not changed in size, but began to jump on one half of the electrode, then on the other. But to both at once - never! It’s just that this is not visible at high frequency, just as flickering of frames on a movie screen is not visible. Optical illusion is simple.
There are no multi-spark candles in nature. True, there were Czech candles “Brisk Premium” in which the discharge jumped from the central electrode to the housing through two intermediate conducting rings in the middle of the insulator, which visually broke the spark into three parts. But in this case, there was only one discharge each time, and not three at all.
Meanwhile, the work of multi-electrode candles is still different from ordinary single-electrode. In addition to increased durability, our comparative tests repeatedly recorded an increase in torque, an increase in effective efficiency, etc.