Abstract: A hydraulic drive carries out a method for discretely changing a positional output on the hydraulic drive. At least one displacement cylinder incrementally supplies or discharges the cylinder volume to or from the drive by displacing the cylinder piston element from a starting to an end position depending on at least one input signal. The piston element is repeatedly displaced from starting to end position and back to discretely change the positional output correspondingly to the supplied or discharged displacement volume. The cylinder is hydraulically connected to a pressure medium source supply or return line while displacing the piston element from starting to end position. The changed positional output is restored in a successive step. The cylinder chambers of the displacement cylinder are hydraulically short-circuited by a short-circuit line hydraulically separated from the supply or return line when returning the piston element from the end to the starting position.

Abstract: A hydraulic drive carries out a method for discretely changing a positional output on the hydraulic drive. At least one displacement cylinder incrementally supplies or discharges the cylinder volume to or from the drive by displacing the cylinder piston element from a starting to an end position depending on at least one input signal. The piston element is repeatedly displaced from starting to end position and back to discretely change the positional output correspondingly to the supplied or discharged displacement volume. The cylinder is hydraulically connected to a pressure medium source supply or return line while displacing the piston element from starting to end position. The changed positional output is restored in a successive step. The cylinder chambers of the displacement cylinder are hydraulically short-circuited by a short-circuit line hydraulically separated from the supply or return line when returning the piston element from the end to the starting position.

Abstract: A hydraulic drive is described for displacing an actuator (7) between two predetermined end positions, comprising a piston unit (4) which can be pressurized in a cylinder unit (3) in opposite directions by way of hydraulic springs and a control device for alternating pressurization in opposite directions of the piston unit (4). In order to provide advantageous constructional conditions it is proposed that the cylinder unit (3) comprises an end section (10) of smaller cross section than the remaining cylinder space (9) and receives in a sealing manner the respective face side (12) of the piston unit (4) in the associated end position, that the end sections (10) connected via a throttle (13) to a return line (14) for the hydraulic medium are delimited by a control edge (11) each relative to the remaining cylinder space (9), and that the control device consists of an actuating drive (28) for an axial relative movement of the control edge (11) relative to the face side (12) of the piston. (FIG.