Abstract: An electro-hydrostatic actuating drive has a variable-volume and/or variable-speed hydraulic machine, which is driven by an electric motor, for the provision of a volumetric flow of a hydraulic fluid. Furthermore, the actuating drive comprises a cylinder with a piston, a piston rod and a first piston chamber, a valve with a first position and a second position, which valve can be moved by a first hydraulic actuator into the first position and by a second hydraulic actuator into the second position, wherein the second position controls a greater volumetric flow of the hydraulic fluid than the first position, a sink, a main line which connects a first piston chamber of the cylinder to the sink and in which the hydraulic machine is arranged, an auxiliary line which connects the first piston chamber to the sink and in which the valve is arranged, a first control line to the first hydraulic actuator, and a second control line to the second hydraulic actuator.

Abstract: An electro-hydrostatic actuating drive has a variable-volume and/or variable-speed hydraulic machine, which is driven by an electric motor, for the provision of a volumetric flow of a hydraulic fluid. Furthermore, the actuating drive comprises a cylinder with a piston, a piston rod and a first piston chamber, a valve with a first position and a second position, which valve can be moved by a first hydraulic actuator into the first position and by a second hydraulic actuator into the second position, wherein the second position controls a greater volumetric flow of the hydraulic fluid than the first position, a sink, a main line which connects a first piston chamber of the cylinder to the sink and in which the hydraulic machine is arranged, an auxiliary line which connects the first piston chamber to the sink and in which the valve is arranged, a first control line to the first hydraulic actuator, and a second control line to the second hydraulic actuator.

Abstract: A displacement control device (1) is adapted to move a member (23) relative to a body (7). The displacement control device includes a drive means (2, 3) and an emergency actuator(8) arranged mechanically in series with the member. The actuator includes a housing (16) and a spring (14) arranged to act between the housing and the member. The improvement comprises: the actuator including a toggle linkage (9) acting between the housing and the spring, the toggle linkage having two pivotally-connected links (10, 11) that are adapted to be selectively moved between a collapsed position at which the links are arranged at an acute included angle, and an extended position at which the links are arranged at an obtuse included angle slightly less than 180°. The toggle linkage is arranged such that the spring will be more greatly compressed when the links are in the extended position than when the links are in the collapsed position.