Abstract: An air cleaning method and apparatus in which air to be cleaned is drawn toward and through a filter (44, 45) along a normal path having a first component extending from a first to a second end of the filter, so as to initially collect particulate matter on the filter, in which momentary pulses of clean air are directed through the filter in a direction opposed to the normal path, to interrupt flow of the air in the normal path so as to dislodge collected particles from the filter and enable migration of the particles toward the second end of the filter, and in which the migrated particles are withdrawn, in a portion of the air, from a site (33, 115) near the second end of the filter.

Abstract: An air cleaning method and apparatus is disclosed in several embodiments. In one set of embodiments, there is described an air cleaning method and apparatus in which air to be cleaned is drawn toward and through a filter in a particular direction. Periodically, reverse pulses of air are directed through the filter in a direction opposite to normal flow to interrupt the flow of air and to dislodge collected particles from the uncleaned air side of the filter and to enable migration of the particles toward the downstream lower end of the filter.In accordance with other embodiments of the present invention, there is described the addition of inertial precleaner devices located proximate the unfiltered side of each filter for inertially separating heavy particulate matter from the uncleaned air prior to filtration.

Abstract: An air cleaning method and apparatus in which air to be cleaned is drawn toward and through a filter (44, 45) along a normal path having a first component extending from a first to a second end of the filter, so as to initially collect particulate matter on the filter,in which momentary pulses of clean air are directed through the filter in a direction opposed to the normal path, to interrupt flow of the air in the normal path so as to dislodge collected particles from the filter and enable migration of the particles toward the second end of the filter, and in which the migrated particles are withdrawn, in a portion of the air, from a site (33, 115) near the second end of the filter.

Abstract: An air cleaning method and apparatus in which air to be cleaned is drawn toward and through a filter (44, 45) along a normal path having a first component extending from a first to a second end of the filter, so as to initially collect particulate matter on the filter, in which momentary pulses of clean air are directed through the filter in a direction opposed to the normal path, to interrupt flow of the air in the normal path so as to dislodge collected particles from the filter and enable migration of the particles toward the second end of the filter, and in which the migrated particles are withdrawn, in a portion of the air, from a site (33, 115) near the second end of the filter.