Dust filtration system

A vacuum loading and cleaning device comprising in combination:

• a tiltable chamber for receiving material, said chamber having inlet means and outlet means,
• a positive displacement vacuum pump connected to said outlet means of said chamber
• hose means connected to the inlet means of said chamber for conveying material from a location remote from said chamber to the interior of said chamber,
• material discharge means on said chamber for discharging material from said chamber when said chamber is tilted,
• filter means interposed between and coupled to said chamber and said pump for filtering the air stream passing therethrough, said filter means comprising:
• a housing having two inlets coupled with said outlet means of said chamber and an outlet coupled to said vacuum pump means,
• air stream directing means within said housing defining two air stream flow paths through said housing, one of said flow paths connecting one of said inlets to said outlet and the other of said flow paths connecting the other of said inlets to said outlet,
• filters in said housing for filtering fine particulate material from the air stream passing through said housing, said filters comprising a first and a second portion, said first portion and said second portion of said filters being arranged in said housing for filtering in series the air stream passing through said first flow path, said second flow path by-passing said first portion of said filters but including said second portion of said filters, and
• means for selectively controlling the air flow from said chamber outlet means to said housing outlet through one of said flow paths.

A device for filtering a high velocity air stream to remove suspended fine particulate materials therefrom said filtering device comprising:

• first and second inlet openings,
• an outlet opening
• a first plurality of tubular fabric filter bags for removing fine particulate material from said air stream,
• a second plurality of tubular fabric filter bags for removing fine particulate material from said air stream,
• means for defining two air stream flow paths through said filtering device, said first flow path including both said first and said second pluralities of filter bags and coupling said first inlet opening and said outlet opening and said second flow path including said seconod plurality of filter bags but bypassing said first plurality of filter bags and coupling said second inlet opening and said outlet opening.