PURPOSE: To increase dust collecting efficiency by detecting generation of reverse ionization, and lowering applied voltage until reverse ionization, is disappeared, and recharging after substantial extinction of residual charge of the dust layer.
CONSTITUTION: Generation and magnitude of reverse ionization are detected by a reverse ionization detecting circuit 13 basing on values of secondary voltage 2 and secondary current 12. Reverse ionization detection signal 16 is given by the detecting circuit 13 and low output instruction 17 is given by an output change timing circuit 15 without delay. A low output setting circuit 18 compares the set value with actual secondary current to render the value predetermined low current value, and controls output 19 so that no difference generates between the two. Output 10 of an automatic voltage controlling device 21 is controlled by the output 19, and secondary current of an electric dust collector EP becomes a previously set value. Reverse ionization disappears at this time.
KAMESHIMA TADASHI
YOKAWA SHINTAROU
YAMAMOTO ICHIROU
| JPS5855060A | 1983-04-01 |