Gerotors

A gerotor is a positive displacement machine element used in pumps and motors. It consists of two intermeshing gears: an inner rotor and an outer stator. The inner rotor has fewer teeth than the outer stator, and its teeth are cycloidal in shape. The outer stator has a trochoidal inner shape that perfectly complements the inner rotor's teeth.

As the inner rotor rotates, the spaces between its teeth and the outer stator's inner surface change volume. These changing volumes create chambers that fill with fluid at the inlet and then decrease in volume, forcing the fluid out at the outlet. The meshing teeth of the inner rotor and outer stator act as seals, preventing fluid from flowing back from the outlet to the inlet.

Gerotor pumps are known for their simple design, compact size, and quiet operation. They are commonly used in various applications, including lubrication systems, hydraulic power units, fuel pumps, and cooling systems. The specific tooth profile and gear ratio determine the flow rate and pressure characteristics of the gerotor. The design ensures a continuous flow of fluid with minimal pulsation. Gerotor mechanisms are efficient and reliable for a wide range of fluid handling tasks.