Dust control system for batch plant charging of transit mixers

Claim 1

In combination with a batch plant for dry-mix material having a discharge outlet through which the material is discharged into the receptacle inlet of a transit vehicle adapted to be positioned in cooperation therewith, a dust-collector shroud connected to the said discharge outlet and adapted to be connected to said receptacle inlet, a filtering unit, and means connecting said shroud to said filtering unit; said filtering unit including a housing divided into first and second separate and independent filter chambers, said chambers having inlets and outlets and filtering means disposed therebetween; first and second electrically-driven exhaust fans mounted in cooperation with the respective outlets of the first and second filter chambers; a common inlet housing chamber connected to said inlets of both filter chambers; said means connecting said shroud to said filtering unit comprising an inlet conduit connected to said shroud and to said inlet housing chamber and having an electrically-actuated inlet valve for controlling flow of dust-laden air therethrough from said shroud to said inlet chamber; and control means connected to said inlet valve and said fans comprising an electric circuit including means for sequentially driving both of said fans and opening said valve to collect dust from the shroud during discharge of material and alternately driving one of said fans and closing said valve to clean the filter material in the chamber in which the fan is not driven by reversing air flow from the outlet of said chamber into said inlet housing chamber.