Rotor 1 rotates about fixed axis A, eccentrically located with respect to the geometric axis of housing 2. Rotor 1 has three slots a in which vanes 3 slide. The vanes have steel balls b at their outer ends and are held constantly against the internal surface of housing 2 by centrifugal force. When rotor 1 rotates, the vanes deliver liquid in the direction of the arrows.
$3801$LHP,RP$