Dust filter apparatus

Claim 1

A dust filter apparatus comprising: a. a bag chamber, b. a head mounted on said bag chamber, c. said head having a dirty air inlet, d. an air plenum mounted on said head with a common wall between said head and said air plenum, e. said air plenum having a clean air discharge opening, f. a back flow air plenum mounted within said head and extending at one end therefrom, g. a multiplicity of walled chambers mounted in said head and extending transversely thereof and through which said back flow air plenum extends, h. a multiplicity of tubular bag supports mounted on and depending from said walled chambers and communicating with said walled chambers and said bag chamber and in alignment with said dirty air inlet, i. each of said tubular bag supports having a filter bag connected to and depending therefrom into said bag chamber, j. means mounted on said back flow air plenum and said common wall for selectively communicating the interior of said bag supports with said back flow air plenum or alternatively with said air plenum and the clean air outlet thereof, said selective means including, k. first ports formed in said back flow air plenum, and l. second ports formed in said common wall in alignment with said first ports, and m. valve means for closing or opening either of said first or second ports, n. means for causing a low pressure area at said clean air outlet to cause air to flow from said dirty air inlet downwardly upon, through and upwardly within said filter-bags and through said head and said air plenum for exit out said clean air outlet. o. means for causing a pressurized reverse air flow condition within the bag supports and outwardly through the bags and downwardly with said first mentioned downward airflow, p. means having apertures through which said bag supports extend, said means being positioned below said dirty air inlet, q. the area of said apertures being sized so as to create a pressure drop between the head and bag chamber thereby forcing the air to be distributed substantially equally across the head and to flow downwardly through the apertures and into the bag chamber, and r. a hopper connected to said bag chamber for receiving collected dust.