Pneumatic transport system and method of transporting articles

A method of transmitting a carrier from a first station wherein the carrier is inserted into a transport conduit to a second station where the carrier is discharged from the conduit, the method comprising:

• exhausting the conduit between the carrier and a closed second gate to create sub-atmospheric pressure in the conduit between the carrier and the second gate to propel the carrier through the conduit toward the second station;
• receiving a signal from a transfer switch connected to the conduit at a predetermined location remote from the first and second stations, indicating that the carrier has passed the predetermined location;
• opening the second gate and closing a first gate between the carrier and the first station in response to the signal from the transfer switch;
• pressurizing the conduit between the carrier and the first gate to create super-atmospheric pressure in the conduit between the carrier and the first gate to propel the carrier through the conduit toward the second station;
• and
• receiving the carrier from the conduit at the second station.

An apparatus for transporting an article through a conduit comprising;

• a conduit extending between a sending station and a receiving station;
• first and second gates remote from the sending and receiving stations for selectively sealing the conduit between a selected one of the gates and the article;
• a pressure source connected to the conduit between the first and second gates for selectively exhausting or pressurizing the conduit to create a pressure differential across an article in the conduit;
• a transfer switch connected to the conduit at a predetermined location between the first and second gates, the transfer switch operative to open and close the first and second gates and actuate the pressure source;
• and
• wherein the conduit between the article and one of the gates is exhausted to propel the article from the sending station toward the transfer switch and the conduit between the carrier and the other of said gates is pressurized in response to a signal from the transfer switch to propel the carrier away from the transfer switch toward the receiving one of the stations.