Oxygen enriched air generation system

#1. Field of the Invention

#The present invention relates to a particular type of oxygen enriched air generation system. A permeable membrane oxygen enriched air and nitrogen gas separation device is utilized. Although the system is particularly suitable for use by dive shops for filling scuba tanks or other types of oxygen enriched air storage vessels, applications in areas such as firefighting, climbing, flight, veterinary, medical and dental treatments, welding, etc., are apparent.

#2. Description of Related Art

#FIG. 1, the only drawing figure provided, illustrates the overall structure of an oxygen enriched air generation system according to the invention.

#A compressed air supply is provided by an assembly 10 of one or more storage vessels. Such storage vessels may include one or more conventional, removable, compressed air storage cylinders 12. Other sources of compressed air, such as a known, oil-free, high pressure compressor (not shown) connected to an alternative compressed air supply branch line 16, may be provided if desired. If a compressor is not attached to the branch line 16, then the branch line 16 may be capped.

#A flow control valve 18 is provided in each branch line 20 connecting an air storage cylinder 12 to a high pressure feed air line 22. A self-contained underwater breathing apparatus (scuba) air tank 14 may also be removably connected to the high pressure feed air line 22, also by a branch line 20 having a flow control valve 18 therein, for reasons which will become apparent. The compressed air is stored in the storage vessels at an initial pressure of anywhere in the range of 3000-6000 p.s.i.g. and, therefore, supplied to the high pressure feed air line 22 at such a pressure. Air flow through the line 22, and air or gas flow through each of the other lines shown in the drawing figure, occurs in the directions indicated by arrows.

#The high pressure air feed line 22 leads from each of the branch lines 16 and 20 to a conventional pressure regulator controlled, by operation of a rotatable knob 24, so as to reduce the pressure of the air supplied by the feed line 22. The pressure regulator is used to reduce the pressure of the compressed air passing into the low pressure feed air line 26 so that it is lower than approximately 600 p.s.i.g. and, typically, in the range of 50-250 p.s.i.g. Air pressure in the low pressure feed air line 26 is monitored by a low pressure side pressure gauge 28 which indicates the air pressure, in p.s.i.g., for example, in the line 26. A flow meter 30 is used to monitor the rate of air flow in the low pressure feed air line 26 and indicates the air flow rate in standard cubic feet per minute (SCFM), for example.