the system of circulation expenses

摘要

A closed tube system is used to guide a number of cars around a fixed path and a series of pumping stations are located around the path. Each station is defined by a fluid flow pump section and a car by-pass section which has its opposite ends associated with the inlet and outlet respectively of the pump section. The pump is operated normally so as to create a tendency for reverse flow of air through the by-pass section so that a car in the section adjacent the pump outlet will be held against a pawl-type stop in the car by-pass section by positive pressure.