An asymmetric linear actuator is provided which integrates a hydraulic dissipater and an electric motor and power screw which generates small forces. The actuator is configured so that an electric motor drives a power screw which drives a rod through a cylinder to provide linear actuation. The cylinder is fluid-filled and incorporates a piston that separates the cylinder into a first and second fluid chamber which are filled with a first and second volume of working fluid. Movement of the piston and rod assembly results in fluid movement between the first and second volumes of working fluid and through the fluidic restriction. The fluidic restriction can be proportionally controllable via an electric motor which enables controllable power dissipation via control of the fluidic restriction motor and controllable power generation via control of the power screw motor.

A braking system including a brake actuator, a control valve, a control assembly, and at least one pressure sensor. The control valve is disposed to direct hydraulic fluid to the brake actuator at a rate corresponding to a magnitude of a control signal. The control assembly includes a mixed-mode control system. The at least one pressure sensor is configured to measure a pressure of the hydraulic fluid to the brake actuator. The control assembly is configured to determine a position of the brake actuator. The mixed-mode control system is configured to determine a position command and a pressure command. The mixed-mode control system is configured to adjust the magnitude of the control signal based on at least one of the position command and the pressure command so as to reposition the brake actuator from a first position to a second position.

An actuator assembly includes an actuation member, a release member, and a source of pressurized gas, wherein during a normal mode of operation, the actuation member and the release member are engaged to move in unison, and wherein during an emergency mode of operation, pressurized gas automatically decouples the actuation member from the release member to move separately. In accordance with yet other aspects of the present disclosure, an electro-mechanical actuator includes an electro-mechanical drive system and an integrated backup system operated by a gas generator, wherein when the backup system is activated, the electro-mechanical drive system is decoupled, and the actuator moves to a predetermined position and mechanically locks in place.

An electrohydraulic device includes an extender which is arranged to be actuated by hydraulic fluid, and a rotor of an electric motor, the rotor being arranged to rotate about a part of the extender. The rotor may have an annular body which encircles or surrounds part of the extender. There is also described a related method of use and a marine vessel or platform where the device may be applied.

An apparatus for converting rotation to fluid flow, comprising a fluid conduit coiled around a rotational axis, the fluid conduit having a first inlet for receiving first fluid having a first density and a second inlet for receiving second fluid having a second density, and a first outlet for output of first fluid and a second outlet for output of second fluid; a motor coupled to the fluid conduit to rotate the fluid conduit around the rotational axis in a first angular direction such that first fluid portions of first fluid and second fluid portions of second fluid are transported along the fluid conduit towards the first outlet, while being pressurized; and a fluid returning arrangement, fluid flow connecting the second outlet and the second inlet for selectively allowing pressurized second fluid to return from the second outlet to the second inlet, while depressurizing the pressurized second fluid.

An asymmetric linear actuator is provided which integrates a hydraulic dissipater and an electric motor and power screw which generates small forces. The actuator is configured so that an electric motor drives a power screw which drives a rod through a cylinder to provide linear actuation. The cylinder is fluid-filled and incorporates a piston that separates the cylinder into a first and second fluid chamber which are filled with a first and second volume of working fluid. Movement of the piston and rod assembly results in fluid movement between the first and second volumes of working fluid and through the fluidic restriction. The fluidic restriction can be proportionally controllable via an electric motor which enables controllable power dissipation via control of the fluidic restriction motor and controllable power generation via control of the power screw motor.

An apparatus for converting rotation to fluid flow, comprising a fluid conduit coiled around a rotational axis, the fluid conduit having a first inlet for receiving first fluid having a first density and a second inlet for receiving second fluid having a second density, and a first outlet for output of first fluid and a second outlet for output of second fluid; a motor coupled to the fluid conduit to rotate the fluid conduit around the rotational axis in a first angular direction such that first fluid portions of first fluid and second fluid portions of second fluid are transported along the fluid conduit towards the first outlet, while being pressurized; and a fluid returning arrangement, fluid flow connecting the second outlet and the second inlet for selectively allowing pressurized second fluid to return from the second outlet to the second inlet, while depressurizing the pressurized second fluid.

An electric motor-driven, rolling element screw linear actuator is presented which work in cooperation with an hydraulic actuator and share several components. This is achieved through the integration of a screw-driven integrated nut piston assembly. Combining the use of an electric screw driven actuator can also reduce the need for a redundant hydraulic system, resulting in the elimination of 50% of connections, valves, piping, pumps, filters etc., while still being 100% redundant. An additional advantage is that the two drive systems are technologically independent, and therefore will not both fail because of an identical component flaw or failure point. The systems may also be used at the same time if conditions require force in excess of that generated by the hydraulic actuator alone.

A screw-pump type electro-hydraulic actuator preferably includes an electric motor device, a hydraulic tube, a pump piston, a spline rod, an actuator rod and a hydraulic control circuit. The electric motor device preferably includes an electric motor and a gearbox. One end of the spline rod is engaged with an output of the gearbox. The pump piston preferably includes a piston base, three sets of screw pump rollers, a spline drive gear, a first piston end plate and a second piston end plate. The hydraulic flow circuit includes a first relief valve, a first check valve, a second relief valve, a second check valve and an accumulator. The screw pump rollers are rotatably retained in the piston base between the first and second piston end plates. The spline gear drives the pump driven gears of the three drive screw pump rollers through the spline drive gear to pump hydraulic oil.

Described is an electrically actuated, pneumatic driven motor. The pneumatic driven motor includes a body having first and second surfaces, the body having a chamber defined by an interior wall, a displacement cavity, and a passage that fluidly couples the displacement cavity to the chamber, a bleeder port and a bleeder port passage that fluidly couples the bleeder port to the chamber, a valve disposed in the passage between the displacement cavity and the chamber, an annular pushrod mechanism coupled to the valve, the annular pushrod mechanism having a pair of pawls that protrude from an inner surface of the annular pushrod mechanism, an axle disposed in the chamber; and a motor gear disposed about the axle, the motor gear having a plurality of teeth that selectively engage with the pawls on the pushrod mechanism according to displacement of the annular pushrod mechanism.