Described is an infusion pump device, comprising a housing (14, 15) which is divided into at least three operating layers positioned one above the other, wherein a first operating layer includes an epicyclic gear means (7, 100, 200) comprising a rotatable central gear (200), a stationary outer ring gear (7) surrounding the central gear, and movable planet gears (100) which are arranged between the central gear and the ring gear (7) and in movable engagement with both the central gear (200) and the ring gear (7), a second operating layer includes a roller bearing means (1, 2, 16) comprising a stationary outer ring (16) and a movable inner roller arrangement (1, 2) which is in movable arrangement with the outer ring (16) and coupled with the epicyclic gear means (7, 100, 200) so as to provide a rotational bearing for the central and planet gears (100, 200), and a third operating layer includes a rotary peristaltic pump means (1, 2, 4) comprising a stationary flexible, preferably resilient, tubing (4) which includes a bent portion having an essentially part-cycle form, and a rotor (1, 2) which is provided with engagement elements (2) for locally engaging the bent portion of the flexible tubing (4) so as to squeeze it during rotation for a pump action, wherein the rotor (1, 2) is coupled with the central gear (200) of the epicyclic gear means (7, 100, 200) so that a torque is transferred from the central gear (200) to the rotor (1, 2).
