Abstract: The accumulator comprises a vessel which is in communication with a hydraulic circuit and which contains a liquid occupying a portion of the space inside the vessel. The level of the liquid contained in the vessel is regulated by controlling the volume of gas overlying the liquid. The regulation apparatus essentially comprise a calibrated injector device for injecting gas under pressure into a first cavity, and a mechanically controlled gas bleeder device in a second cavity separated from the first cavity by a partition having at least one calibrated orifice situtated in a zone which is safe from being submerged in the liquid, and an opening situated in the liquid level control zone and extending on either side of the level of the interface between the liquid and the gas.