Abstract: A method and an apparatus for controlling airflow in a desiccant drying system having a plurality of desiccant beds, in which each desiccant bed is located in a chamber, and multi-position valves can be operated to cause the gas to be dried to flow in a serial manner through a plurality of desiccant bed chambers while another desiccant bed is isolated from the gas flow and undergoing regeneration. Once regenerated, the multi-position valves are repositioned to establish a new serial flow gas path in which the freshly regenerated desiccant bed becomes the final bed in the series, and another bed undergoes regeneration.

Abstract: A vacuum receiver for a pneumatic conveyor for conveying, e.g., plastic pellets, having a receiving vessel with a material inlet, a material outlet and a conveying gas outlet. A first valve member is provided for opening and closing the conveying gas outlet, and a second valve member is provided for opening and closing the material outlet. Both valve members are connected to a common valve shaft and actuated by a single actuator mounted on a vessel lid. The vacuum receiver of the invention has the advantage of affording positive control and sealing of the material discharge valve while at the same time being economical to manufacture and easily cleaned.

Abstract: A safety system of roll guards protecting an anesthesia machine's wheel assemblies from being obstructed or snagged by objects lying upon a floor surface or dangling above the floor surface that are in the path of movement. Each roll guard is loosely connected to part of the wheel assembly or anesthesia machine, and has a vertically upstanding cylindrical portion whose bottom rests upon the floor surface. The cylindrical portion surrounds and freely receives therein the wheel assembly, and has a top portion closed by a cap.