Rotor 1, having four rigid vanes a, rotates about a fixed axis, eccentrically located with respect to the geometric axis of housing 2. Four cylinders 3 can roll and slide freely along the internal surface of housing 2 and along vanes a. When rotor 1 rotates, cylinders 3 are held constantly against the internal wall of housing 2 by centrifugal force, forming the necessary seals between the rotor and housing.
$3792$LHP,RP$