Abstract: Drive mechanism for the conversion of oscillatory motion into rotating motion or vice versa by means of a non-circular gear train, in a system composed of arcuate pistons solidly fixed to a rotor which is able to oscillate about its axis inside a stator. The mechanism comprises a set of non-circular internal and external toothed gears coupled in a fashion similar to that of two epicyclic gearings joined by their respective planet gears, although there are not any sun gears in the present arrangement. All the gears cooperate so as to produce the sought motion conversion between the pistons and the planet carriers and the drive shaft attached thereon. Its field of application includes therefore any device that uses variable volume chambers as a means to transmit energy to, or obtain energy from, a working gas, such as compressors, pneumatic motors or internal combustion engines.

Abstract: Drive mechanism for the conversion of oscillatory motion into rotating motion or vice versa by means of a non-circular gear train, in a system composed of arcuate pistons solidly fixed to a rotor which is able to oscillate about its axis inside a stator. The mechanism comprises a set of non-circular internal and external toothed gears coupled in a fashion similar to that of two epicyclic gearings joined by their respective planet gears, although there are not any sun gears in the present arrangement. All the gears cooperate so as to produce the sought motion conversion between the pistons and the planet carriers and the drive shaft attached thereon. Its field of application includes therefore any device that uses variable volume chambers as a means to transmit energy to, or obtain energy from, a working gas, such as compressors, pneumatic motors or internal combustion engines.