| 摘要 |
<p>PURPOSE:To always purify one of two passages in a filter block composed of stacked elements in two stage, each having an electrical heater, by alternately selecting the two passages so as to burn deposit in the two passages. CONSTITUTION:In addition to a filter block 2 composed of two groups of filters 21 and filters 26, each group incorporating an electrical heater, a filter block 3 having a structure similar to that of the filter block 2 is provided. Accordingly, air is fed into the filter blocks 2, 3 by a blower 5, and exhaust gas is alternately fed to the filter blocks 2, 3 by switching a shutter 4. If clogging occurs due to trapping of particulate, a pressure sensor 61 detects the clogging condition so as to change over the flow passage one to the other of the two passages, and deposit is burn by energizing the heater and is blown by the blower 5 so as to eliminate the clogging.</p> |
