Method and apparatus suitable for heating relatively poorly conducting substances

摘要

Poorly conducting substances, such as chips of cellulose material containing a heat hardenable binder, are heated by passing them between the plates of an operational capacitor supplied with energy from a high frequency generator. An adjustable auxiliary capacitor is connected in parallel with the operational capacitor and is adjusted to match the capacity of the output circuit to the generator with changing conditions of the poorly conducting substances. Coarse initial control is effected by adjusting the separation of the plates of the operational capacitor. The apparatus is especially useful for making chip boards and the like in which a precompressed mass of chips is passed between the plates of the operational capacitor sandwiched between two endless belts.