Circular rotor 1 rotates about eccentrically located axis A, coinciding with the geometric axis of housing 3. Rotor 1 is encircled by split collar 2 whose rounded ends a slide along fixed partition d of housing 3. When rotor 1 rotates, collar 2 slides along internal surface b of housing 3 and delivers liquid in the direction of the arrows.
$3830$LHP,RP$