Patent ID: 8640855

Claim:
A dust control apparatus for a bulk material handling transfer system comprising: a chute comprising a pathway there through for handling varying volumes of bulk material flowing through the chute using gravity flow; the chute further comprises an entrance zone and an exit zone, wherein a flow of material is received into the chute at the entrance zone from a transfer chute that receives the material via a discharge conveyor, and the material passes through exit zone of the chute into the transfer chute and is expelled onto a receiving conveyor; a self-adjusting air restrictor gate pivotally mounted inside the chute for engaging flowing bulk material for restricting the air pathway during material volume flow variations; said air restrictor gate having a mounting system to allow the air restrictor gate to maintain contact with the flowing bulk material through the chute to close off any air gap and to vary the size of the pathway in response to the change in volume of flow of bulk material through the chute and to restrict the flow of air through the chute and around the air restrictor gate to reduce dust emissions; the air restrictor gate comprises a gate member that is pivotally mounted off center so that it hangs from an upper wall of the chute in a neutral position partially closing off the chute pathway when no bulk material is flowing through the chute, and it contacts the upper surface of flowing bulk material and to eliminate any gaps in response to the flow of bulk material through the chute to restrict the flow of air through and out the chute to reduce dust emissions; the chute comprises an upper wall portion and a lower wall portion; the air restrictor gate member is pivotally mounted to the upper wall portion so that it hangs in the neutral position when no bulk material is flowing through the chute, and moves up and down in response to engagement with the upper surface of flowing bulk material through the chute to restrict the flow of air to reduce dust emissions; a counterweight mechanism to help control the movement of the air restrictor gate when varying amounts of flowing bulk material contacts the lower portion of the air restrictor gate; and the mounting system comprises a rotatably mounted shaft that is connected to a damper shock absorber to help maintain controlled contact of the air restrictor gate with the upper surface of bulk material flowing through the chute.