Pneumatic transmission system

A pneumatic transmission system for free deliver of a carrier from the system comprising:

• a terminal;
• a closure on said terminal being adapted to allow placement of a carrier in the terminal;
• a transmission tube having a first end communicating with said terminal and a second open end spaced from said terminal;
• air supply means being adapted to supply pressurized air and to supply a partial vacuum;
• a first line communicating between said air supply means and said terminal;
• a first check valve in said first line being adapted to allow pressurized air from said air supply means to flow into said terminal;
• a second check valve in communication between said transmission line and said first air line being adapted to open when a partial vacuum from said air supply means is applied to said first air line;
• a second air line having a first end communicating with said air supply means and a second end communicating with the transmission tube immediately adjacent said second open end;
• a third check valve in communication between said second air line and said transmission tube, said third check valve being positioned a predetermined distance from said second open end of said transmission tube and being adapted to open when a partial vacuum is applied to said second air line by said air supply means;
• and a control valve positioned in said second air line between said third check valve and said second end of said second air line being adapted to control the flow of pressurized air between said third check valve and said second open end of said transmission tube such that the air pushing a carrier through said transmission tube is controlled to allow deceleration of the carrier prior to exiting the second open end of the transmission tube.

A free delivery transmission system to move a carrier comprising:

• a terminal which is open to ambient atmosphere;
• a transmission line having an open end communicating with said terminal;
• a reversible blower adapted to supply pressurized air to an outlet and to draw a partial vacuum at an inlet;
• a return line connected between the inlet of the blower and the transmission line at a location remote from said terminal such that a partial vacuum is formed in the transmission line to move a carrier away from said terminal;
• and a supply line connected between the outlet of the blower and the transmission line adjacent the open end of the transmission line such that air from said supply line will maintain pressure in said transmission line at or above atmospheric pressure to prevent flow of ambient air from said terminal into said transfer tube.