Unidirectional thrust air cycle machine arrangement with asymmetric thrust bearings

An air cycle machine (ACM), comprising:

• first and second rotors, each of the first and second rotors comprising rear and forward faces and a central portion interposed between the rear and forward faces with outwardly extending blades;
• a shaft connecting the first and second rotors;
• one or more first bearings disposed on the shaft to support shaft rotation;
• a second bearing disposed on the rear face of the first rotor;
• and
• a third bearing disposed on the forward face of the first rotor.

A method of assembling an air cycle machine (ACM), the method comprising:

• forming first and second rotors, each of the first and second rotors comprising rear and forward faces and a central portion interposed between the rear and forward faces with outwardly extending blades;
• disposing one or more first bearings on a shaft;
• disposing a second bearing on the rear face of the first rotor;
• disposing a third bearing on the forward face of the first rotor;
• and
• connecting the first and second rotors by the shaft.