| 摘要 |
An evaporation heater having a wire wound into a coil and a support wire which extends from one arm of the wire outside of the coil, in spaced proximity therewith, to a central position within the coil but out of electric contact therewith is disclosed. An annular pellet of evaporant material is positioned over the wire support arm within the heater coil but out of contact therewith. The atmosphere around the heater coil and pellet is substantially evacuated and current is directed through such coil to apply radiant heat to the pellet to evaporate same. Because the heater coil is in spaced proximity with the pellet of evaporant material and not in contact therewith, chemical reaction therebetween or erosion is avoided, and a durable evaporation heater of uncomplex construction is provided.
|
