A camshaft phaser assembly, including: an axis of rotation; a hydraulic camshaft phaser including a stator arranged to receive rotational torque and including a plurality of radially inwardly extending protrusions, a rotor arranged to be non-rotatably connected to a first camshaft and including a plurality of radially outwardly extending protrusions circumferentially interleaved with the plurality of radially inwardly extending protrusions, and a plurality of chambers bounded at least in part by the plurality of radially inwardly extending protrusions and the plurality of radially outwardly extending protrusions; an electric camshaft phaser including an output gear arranged to be non-rotatably connected to a second camshaft located concentrically within the first camshaft and an input non-rotatably connected to the stator; and a connection plate non-rotatably connecting the input and the stator. The rotor and the output gear are rotatable with respect to each other about the axis of rotation.

Fail-fixed hydraulic actuator systems for aircraft include a hydraulic actuator having a piston in a housing. The piston separates the housing into a retract cavity and an extend cavity. A sleeve is moveably arranged within the housing and includes a sleeve aperture that is aligned with a piston head during normal operation. A driving mechanism is configured to drive movement of the sleeve to maintain alignment between the sleeve aperture and the piston head. A low pressure cavity is defined between an interior surface of the housing and the sleeve and, when the piston head is offset from the sleeve aperture, the low pressure cavity is hydraulically connected to one of the retract cavity or the extend cavity to cause a pressure differential with the other of the extend cavity and the retract cavity and cause movement of the piston head to align with the sleeve aperture.

Disclosed herein are hydraulic actuators and methods for the operation of actuators having variable relative pressure ratios. Further disclosed are methods for designing and/or operating a hydraulic actuator such that the actuator exhibits a variable relative pressure ratio. In certain embodiments, the relative pressure ratio of the hydraulic actuator may be dependent on one or more characteristics (such as, for example, frequency or rate of change) of an oscillating input to the hydraulic actuator.

[Object] To provide a compact, high-output actuator device allowing force control.

[Solution] An actuator device 1000 includes an electromagnetic coil member 110 provided over a prescribed width on an outer circumference of a cylinder 100, and a movable element 200 slidable as a piston in the cylinder 100. The movable element 200 has a magnetic member 202, and is moved relatively by excitation of the electromagnetic coil member 110. Fluid is supplied to first and second chambers 106a and 106b such that when the movable element 200 is to be moved relatively, the movable element 200 is driven in the same direction.

An electromechanically drivable brake pressure generator for a hydraulic braking system of a vehicle, including an electric motor unit, which is activatable with the aid of an electronic control unit in accordance with a brake pressure to be applied and whose rotary motion generated thereby is converted by a reducing gearbox unit including an output-side spindle drive unit into a translatory motion for actuating a piston of a hydraulic piston/cylinder unit. A hydraulic block of the piston/cylinder unit also at least partially accommodates the electric motor unit in such a way that a motor shaft of the electric motor unit extending at least predominantly in the area of the hydraulic block is situated axially parallel to a longitudinal axis of the piston of the piston/cylinder unit which is movable in the hydraulic block.

Disclosed herein are hydraulic actuators and methods for the operation of actuators having variable relative pressure ratios. Further disclosed are methods for designing and/or operating a hydraulic actuator such that the actuator exhibits a variable relative pressure ratio. In certain embodiments, the relative pressure ratio of the hydraulic actuator may be dependent on one or more characteristics (such as, for example, frequency or rate of change) of an oscillating input to the hydraulic actuator.

A hydraulic actuator includes a hydraulic cylinder; a piston within the hydraulic cylinder and movable in response to movement of hydraulic fluid in a hydraulic circuit coupled to the hydraulic cylinder; a synchronisation connection for receiving an input from a simultaneous transmission line; and a valve for controlling the flow of hydraulic fluid in the hydraulic circuit. The valve is a rotary valve comprising: a first valve section arranged to rotate in either a first rotational direction or a second rotational direction in response to input from the simultaneous transmission line in order to open a hydraulic flow path to the cylinder and urge the piston to move along the hydraulic cylinder in a corresponding first linear direction or second linear direction; and a second valve section arranged to rotate in either the first or second rotational direction.

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.

Transmissions, filter assemblies for transmissions, and valve assemblies for transmissions are disclosed herein. A transmission includes an input shaft, an output shaft, and a hydraulic system. The input shaft is configured to receive rotational power supplied by a drive unit. The output shaft is coupled to the input shaft and configured to provide rotational power supplied to the input shaft to a load. The hydraulic system is configured to supply fluid to one or more fluid demand devices coupled between the input shaft and the output shaft in one or more operating modes of the transmission. The hydraulic system includes a filter assembly having a filter element and a valve assembly fluidly coupled to the filter element.

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.