Apparatus For Controlling Vehicles Moving Through A Conduit By Air

Abstract

An apparatus for controlling vehicles which are moved through a conduit by air and includes a processing system positioned in the conduit for collecting, storage and dispatching the vehicles in which an air pump is positioned in parallel with the processing system having its suction connected to the conduit upstream of the system and its discharge connected to the conduit downstream of the system. Valve means are connected to the conduit for reducing the tendency of the vehicles in the processing system to move upstream towards the pump suction. The valve means alternates the pressure in a portion of the processing system between less than atmospheric and at least atmospheric. One form of the valve means may include an air blocking vehicle stop movable into and out of the conduit and a valve connected between the conduit and the atmosphere upstream of the vehicle stop which is open and closed in synchronism with the vehicle stop. In addition, a second valve may be connected between the conduit and the pump suction upstream of the air blocking vehicle stop for speeding up the vehicle processing. In another embodiment, first and second swingable flap valves may be positioned in the conduit in the upstream portion of the processing system with an air flow control connected to the pump suction and positioned for alternately withdrawing air from the conduit upstream of each of the first and second valves for allowing the vehicles to pass through the flap valves, but preventing the application of the pump suction to the conduit downstream of the second valve.