Abstract: A fully variable hydraulic valve drive comprising a hydraulic drive unit which is acted upon with hydraulic fluid for opening and closing a valve wherein the drive unit of the valve in the closing or opening stroke movement acts on an intermediate storage means with hydraulic fluid under pressure, wherein this hydraulic fluid which is stored under pressure in the intermediate storage means then drives the drive unit of the valve again in the opposite stroke movement.

Abstract: A device for controlling a hydrostatic drive (1) having a resonator (2) which is connected on the one hand to the hydrostatic drive (1) and on the other hand to a pressurized-fluid supply line (4) and to a return line (5), and having a periodically actuatable switch valve (3) which connects the resonator (2) alternately with the pressurized-fluid supply line (4) and the return line (5). In order to assure advantageous control conditions, the resonator (2) has at least one pressure chamber (6) with a movable, oscillatable chamber limitation (7) for changing the chamber volume movable chamber limitation (7) form a part of a single-mass oscillator comprising mass and spring (10). The pressure chamber (6) which can be connected alternately with the pressurized-fluid supply line (4), the return line (5) and the hydrostatic drive (1) can be acted on via the switch valve (3) with a switch frequency which lies in the supraresonance region of the single-mass oscillator.