Abstract: The invention related to a method for low loss periodic control of a capacitive load (CP), in particular of a piezoelectric actuator. In this method, before load control begins, a capacitor bank (C1) is charged via a voltage source (UB) until the oprating voltage of load (CP) is attained; then the load (CP) is charged from the capacitor bank (C1) via a series resonant circuit formed by a reactance coil (L1), a freewheeling diode (DE), and by the load (CP). In this method, when a load is required, the load (CP) is linked via discharge switch (SE) to the reactance soil (L1) which is itself connected via a freewheeling freewheeling diode (DL) to the capacitor bank (C1) in such a way that the load (CP) is discharged until a residual voltage (UR).

Abstract: A hydraulic control valve includes a valve housing defining a valve chamber having first and second axially spaced valve seats of identical diameters, a control cylinder and first and second end cylinders. The valve chamber, the control cylinder and the first and second end cylinders are axially arranged in a series and form a cavity. A first pressure conduit communicates with the control cylinder, a second pressure conduit communicates with the first end cylinder, a third pressure conduit communicates with the second end cylinder; a control conduit communicates with control cylinder; and a discharge conduit communicates with the valve chamber.

Abstract: A fuel injection valve for an internal combustion engine includes a valve block; an injection nozzle carried by the valve block and having a nozzle opening; a valve needle slidable in the injection nozzle for assuming closed and open positions to block and, respectively, to unblock the nozzle opening; a closing spring urging the valve needle into the closed position; and a pressurized fluid port in the valve block. The nozzle opening is in communication with the pressurized fluid port in the open position of the valve needle. A discharge port is defined in the valve block for carrying fluid away therefrom. An equalizing piston, which is slidably disposed in a work chamber in the valve block, is connected with the valve needle. A control plunger is movable in the valve block and has a first position and a second position.