Abstract: A self-contained dust collector which includes a quick release adaptor duct mounted between a filter unit and a storage receptacle for conveying dust to the receptacle with the quick release adaptor duct comprising a planar member having a central opening and a plurality of pleats which permit the outer periphery of the planar member to either be (1) lengthened as the planar member is moved from a closed duct forming position in which the duct provides a sealed transition duct for conveying dust into the receptacle to an open nonduct forming position spaced away from the receptacle or (2) shortened as the planar member is moved from the open nonduct forming position into the closed duct forming position in which the outer periphery of the planar member is placed under tension to maintain the periphery in sealed relation to the receptacle.

Abstract: A filter apparatus including a housing having a discharge apparatus for removing granular gas treating material from the hopper of the housing. The discharge apparatus includes a baffle plate extending across the hopper between the side walls of the housing which defines a material discharge channel opening into the interior of the hopper through a pair of parallel slots extending along the edges of the baffle plate, a conveying gas inlet aperture in one of the side walls opening into one end of the conveying channel, and a gas treating and conveying gas outlet aperture in the other side wall opening into the other end of the conveying channel of a larger cross-sectional area than the conveying gas inlet aperture to promote progressive aspiration of the treating material from the interior of the hopper commencing at the end of the channel proximate the conveying gas inlet aperture.

Abstract: A sealing device for a plurality of flow-through filter cells in a filter cell housing including a longitudinally extending toggle joint support member extending through opposed side walls of the housing and a plurality of toggle joints mounted at the knees onto the toggle joint support member, the toggle joints having one end pivotally mounted to the frame of the housing and the other end including engaging means engageable with the filter cells upon longitudinal movement of the support member.

Abstract: A door latch device for securing a door in place closing an opening into an enclosure including an elongated resilient retainer strap having an elongated aperture formed in one end and attachable at its other end to the door, a threaded screw-type fastener with a shoulder formed on its shank having its threaded shank extending through the elongated aperture with the shoulder in abutment with one side of the retainer strap, and a latch plate having a concave depression with a centrally disposed threaded aperture therethrough to receive the threaded shank of the screw-type fastener. The screw-type fastener is held in place in the elongated aperture by a resilient toroidally shaped keeper which fits over the shank of the screw-type fastener on the other side of the retainer strap from the shoulder. The latch plate is attachable to the enclosure adjacent the opening to be closed by the door.

Abstract: A control circuit for an automatic roll-type air filter including a photocell for detecting the dust load condition of the filter media and for energizing the circuit to cause the filter media to advance in response to the dust loading, a variable resistor to provide adjustment of the set-point at which the circuit is energized, and a fixed value resistor in series with the variable resistor to prevent setting of the variable resistor to a value which would allow the circuit to be energized thereby advancing the filter media when cleaned media is present in the air filter zone of the automatic roll-type air filter.