電極距離2．0mm以下及び電流0．2A以下の炭素アーク継続時間

摘要

Metallic arcs become unstable at currents near the minimum arc current; and their duration becomes short. This study investigates whether carbon arcs reveal the same phenomena. Arc discharge durations were measured at electrode gaps shorter than 2.0 mm, and at currents lower than 0.2 A; the effects of gap lengths and currents on mean arc durations were examined; as a result, the current was found to be more effective than the gap length. Arc duration was about 10 ms at 0.1 A; it became shorter when the current became lower; and it was about 60 μs at 0.04 A.%金属アークでは最小アーク電流付近でアークが不安定になり、持続時間が短くなる。炭素アークでも同様の現象が見られるかを調べている。間隙2.0mm以下、電流0.2A以下でアーク放電継続時間を測定し、電流と電極間距離に対する継続時間平均値を調べた結果、電極間距離よりも、電流の影響が大きいことがわかった。継続時間は0．1Aで約10msとなり、電流とともに減少し、0.04Aでは約60μSであった。