Bag collector for dirt with selective half-bag cleaning

A bag collector for removing particles carried in a dirty stream of gas, comprising a housing, a plurality of elongated tubular porous filter bags mounted in said housing in a straight line side by side with their longer dimensions parallel, all of said bags closed at the same one end and open at the other end, a first limiting partition in said housing extending entirely across said housing at the open tops of said bags and defining a clean gas chamber on one side thereof and a dirty gas chamber on the other side, thus confining said dirty gas to impinge on the lower ends of said bags up to a zone near the tops of said bags, said first limiting partition having openings to which said open ends of said filter bags are attached, a second partition spaced from and parallel to said first limiting partition in said clean gas chamber and extending entirely across said housing and being imperforate except for first clean gas openings between each two adjacent bags in said line and openings opposite each open end of each bag, third guiding partitions extending in line with each bag parallel to the bag center line between said first limiting partition and said second partition, an inlet through said housing to introduce under pressure a stream of dirty gas into said dirty gas chamber of said housing outside of said bags, a discharge means for clean gas extending entirely across said housing and parallel and spaced from said second partition on the side thereof opposite said first limiting partition, said gas discharge means being imperforate except for second clean gas openings one opposite each said first clean gas openings, a substantially impervious linear fourth partition in the middle of each bag normal to said straight line of bags dividing the inside of each bag into two non-communicating half portions extending from end to end of each bag, said fourth partition extending beyond the open ends of each bag through said second partition and to said discharge means, a first valve means mounted in said housing for movement to close and open each of said second clean gas openings in communication between said discharge means and individual open ends of adjacent half portions of said bags, means for selectively opening and closing said first valve means, a duct for cleansing gas under pressure communicating between each two bags in said line and between said first limiting partition and said second partition, second valve means mounted in said housing for movement to close and open each of said first clean gas openings communicating between said duct for cleansing gas and said individual open ends of adjacent half portions of said bags, means for selectively opening and closing said second valve means when said first valve means is respectively closed and opened, and means for collecting dirt from said bags in the bottom of said housing, said partitions in said housing and said valves permitting clean air from the tops of adjacent half-bag portions to pass out said discharge means only when said first valve means is open and for causing said cleansing gas to pass into the open tops of adjacent half-bag portions only when said second valve means is open, whereby said first valve means may be closed and said second valve means may be opened in relation to a selected pair of two adjacent half portions of said bags to dislodge dirt particles on the outer surfaces of said two half portions to fall downwardly in relative quiescent state while other half portions of the same and other bags are collecting dirt particles.