High frequency HF
It is a technology developed over the years by TVM for plastic heating or bonding, it operates by bringing the plastic at very high temperatures in a few seconds.
The high frequency generator is composed of a cell containing a thermionic valve, called triode, capable of transforming the electricity frequency from 50 Hz up to 27MHz.
The generator is then composed of two transformers: one at low voltage, which feeds the valve, and one at high voltage, that supplies the power to be converted into high frequency. The latter is then conducted to an anode which rests on the workpiece to be heated: in this way the circuit closes on the cathode which is located at the opposite end of the anode, by placing between the two electrodes the part to be heated.
This system is absolutely safe thanks to the shielding of the cell and the generator. There are also safety circuits which ensure the anti-shock in the event that there is electrical continuity between the anode and cathode, as well as the overload in case the power is adjusted to an excessive level.