Researchers at Engineair Pty Ltd. (Melbourne, Australia) have designed a rotary air engine called the Di Pietro motor, whose concept is based on a rotary piston and is driven by compressed air. The motor uses a cylindrical rotary piston that rolls inside the cylindrical stator. The space between stator and rotor is divided into six expansion chambers by pivoting dividers. These dividers follow the motion of the shaft driver as it rolls around the stator wall.
The unit is lighter than piston motors and produces no fumes. The compressed air would be held in tanks mounted under the loading floor of ground-based vehicles. Engineair plans to develop a new burden carrier, driven by the motor, for use on a small scale.
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