Abstract: A flow regulator that always guarantees the same rate of flow independently from the admission pressure is provided. This is achieved by a piston (26), which is mounted movably in the direction of flow and is loaded by an elastic element (29) in the direction opposite the direction of flow, being arranged in a housing (10) of the flow regulator. An annular space around the piston (26) is reduced due to the movement of the piston (26) in the direction of the flow. This flow regulator has a strong throttling action in the case of high admission pressure and a weak throttling action in the case of low admission pressure, so that the rate of flow is always maintained at a constant value.