| 摘要 |
A fluid assisted doffer (30) is disclosed in combination with a fluid filter (10). The fluid filter (10) includes a rotatably mounted drum (23) covered with a filter screen (25). Fluid is filtered through screen (25) from the upstream to the downstream side to form an overlying porous layer of particulate matter. The downstream side of the drum (23) includes filter chambers (A) and (B) being sealed against direct fluid flow. The fluid assisted doffer comprises a doffing chamber (45) positioned on the downstream side of screen (25) at the position where the overlying porous layer of particulate matter is to be removed from the screen (25) and communicating through the screen (25) with the upstream side thereof. The doffing chamber (45) is sealed against direct fluid communication with filter chambers (A) and (B) on the downstream side of the screen (25). Fluid is diverted from the upstream side of the screen (25) therethrough, into the doffing chamber (45) and out of the doffing chamber (45) through the screen (25) and against the underside of the overlying porous layer particulate matter. The fluid thereby mechanically assists the porous layer of particulate matter in being removed from the screen (25). |
