Abstract: A control system for a conveyor having a plurality of trolley carriers movable along a path of travel and having at least one latching type reed switch whose open or closed condition is sensed in a reading station through which the trolley carrier moves, to effect some desired control function with respect to the trolley carrier. At another station, such as a writing or reset station upstream of the reading station, the switches are latched in an open or closed condition which accompanies the trolley carrier during movement of the trolley carrier along the path of travel and through the reading station. The writing station has a plurality of permanent or electromagnets conditioning each switch separately and remotely; and a reset station may be provided upstream of the writing station for separately initiating each carrier switch to an inoperable condition.

Abstract: A power and free conveyor has a stop lug on the carrier body adapted to abut a stop member movable into the path of the carrier along the conveyor track to arrest movement of the carrier, the stop member serving to disengage the driving dog from the power chain prior to abutting the stop lug. The stop lug is spaced rearwardly of the driving dog a distance exceeding rebound of the carrier whereby accidental re-engagement of the driving dog with the power chain is avoided. The stop lug is positioned to engage the power chain pusher lug on a decline in the conveyor system should the hold-back dog fail to do so, thereby preventing a runaway.

Abstract: A gas scrubber of the wet collector type induces a gas flow under a negative pressure through a housing between a gas inlet and a gas outlet. The housing includes a scrubbing liquid reservoir, and means in the housing cooperating therewith to define a gas scrubbing zone above the reservoir and through which the gas moves. A tunnel open to the atmosphere extends transversely of the housing adjacent the scrubbing zone with the interior of the tunnel being at atmospheric pressure, which is higher than the gas pressure in the housing. A spinner shaft in the tunnel projects through the tunnel wall and carries a liquid diffusing spinner in the scrubbing zone. The shaft is solely supported by bearing means in the tunnel. A pump draws liquid from the reservoir and directs it against the spinner to diffuse the liquid across the scrubbing zone. By virtue of the higher pressure in the tunnel the bearings supporting the spinner are not contaminated by the scrubbing action in the housing.