Operation principle of micro annular gear pumps


Both rotors, which are eccentrically mounted, are intermeshed with their cycloid gearing. As a result a system of several sealed pumping chambers exists at all times. With a tooth ratio of 6/7, a chamber number of six results.

The shaft of the micro annular gear pump is connected to the internal rotor and is powered by a precisely controlled electric motor. The external rotor is mounted rotatable and is driven by the internal rotor.

As the rotors turn around their offset axes, the volume of the pumping chambers increases on the induction side and simultaneously decreases on the delivery side of the pump. A homogeneous and low-pulsation flow rate is generated between the kidney-shaped inlet and outlet which also combines several pumping chambers at the same time. The pump’s conveying direction is reversible, however, a recommended direction of rotation exists.