ATF® Features and Benefits

The ATF is simple, compact and eliminates up to 60 pneumatic connections and 30 electrical connections found in conventional concentrators. The compact, lightweight design of the ATF allows reduction of size and mass of the complete concentrator.

The acoustic signature of the ATF is profoundly different from conventional concentrators. The ATF breaks the relatively large impulsive sound of purging a conventional two-bed unit into many smaller amplitude impulses, which are inherently easier to silence. In addition, the noise generated by the compressor supplying air to the ATF is less objectionable because of the small variation in compressor pressure.

The ATF's pressure characteristics reduce wear on compressor components. In conventional oxygen concentrators, the compressor is often the most wear- and fatigue-prone component in the system.The imposition of continual large cyclic changes in output pressure results in transient vibratory loads on the intake and exhaust flapper valves in the compressor, causing metal fatigue and reduced operating life. These same pressure fluctuations also result in cyclic variation in compressor speed, which lead to greater wear and reduced life of the ball bearings supporting the motor shaft and pistons.

ATF® Oxygen Concentrators

Endurance testing of ATF's has confirmed these benefits. One compressor was run continuously for 24 hours per day for 1.5 years without failure while operating a prototype ATF. In this period of time, an equivalent compressor in a conventional oxygen concentrator would have required at least one overhaul.

The control valves and electronic control circuits of conventional oxygen concentrators are also trouble-prone components. When they malfunction, collateral damage to the system, including sieve bed failure, often results. The ATF's continuously rotating, motor-driven distributor valve is markedly simpler and inherently more reliable than the valves used in conventional concentrators. The rotary valve turns slowly, at only two revolutions per minute. The valve comprises a flat pressure-balanced graphite rotor mated with a flat silicon carbide stator plate. The flat valve faces continuously lap themselves together. Because of the low rubbing speed, wear is negligible. Testing of the valve has shown that it will have an almost indefinite life.

In addition to the ATF's benefits of reliability enhancement, it also has marked improvements in performance at high oxygen flow rates.

With equivalent compressors and similar quantities of molecular sieve in the systems, the ATF is capable of delivering much higher purity oxygen at higher flow rates than conventional two-bed concentrators. This figure shows a comparison of a 5 liter per minute (lpm) capacity conventional oxygen concentrator with a 5 lpm ATF system. Note the divergence in oxygen concentration at flow rates above 5 lpm.