A ballscrew actuator comprises a ballnut having at least one first helical groove formed on a radially inner surface and defining an axis (X), a ballscrew disposed along the axis (X) within the ballnut, the ballscrew having at least one second helical groove formed on a radially outer surface and opposed to the first helical groove so as to form at least one helical raceway and a plurality of balls or rolling elements disposed in the at least one helical raceway. The ballscrew is movable relative to the ballnut between a stowed position and a deployed position. The ballscrew comprises a ballscrew bore extending axially therein. A lubrication piston is mounted for sliding movement within the ballscrew bore and divides the ballscrew bore axially into a lubricant receiving portion and a pressurising portion.

An actuator includes a housing, an extension arm, and a threaded spindle. The threaded spindle is mounted on the housing in such a way as to be rotatable with respect to an axis of rotation by a first rotary bearing. The extension arm projects out of the housing in such a way that it can be moved in a direction of the axis of rotation. The housing and the extension arm together delimit an internal space, the volume of which changes when the extension arm moves. A first end of the threaded spindle that is remote from the first rotary bearing, projects into a tubular section of the extension arm, irrespective of a position in which the extension arm is situated. The tubular section extends with a constant internal cross-sectional shape along the axis of rotation.

A ball screw device includes: a screw shaft that has a first screw groove on an outer circumferential surface thereof; a cylindrical nut member that has a second screw groove on an inner circumferential surface thereof; plural rolling elements that can roll in a rolling path formed between the first screw groove and the second screw groove; and a lubricant applied to the rolling path, wherein the lubricant has a loss tangent tanδ larger than 0.11, which is measured by dynamic viscoelasticity measurement performed at a temperature of 25° C., an angular frequency of 10 rad/s, and an amount of strain of 0.01%.

The invention relates to an actuator (1) comprising: a body (4), a first element (5) mounted such that it can move rotatably in relation to said body (4), and a second element (6) mounted such that it can move translatably in relation to said body (4), either the first element (5) or the second element (6) being a screw and the other one being a nut, the nut cooperating with the screw such that a rotation of the first element (5) in relation to the body (4) around an axis of rotation (X) causes the translation of the second element (6) in relation to the body (4) parallel to the axis of rotation (X), a cylinder which is stationary in relation to the first element (5), a piston mounted such that it can move translatably inside the cylinder between a first end position and a second end position, and a cam surface which is stationary in relation to the body (4) and against which the piston is supported such that a rotation of the first element (5) in relation to the body (4) causes a translatory back-and-forth movement of the piston between the first end position and the second end position.

An electric actuator 1 includes a drive unit 2, a driving force transmission mechanism 3, a motion conversion mechanism 4, an accommodation space accommodating the drive unit 2, the driving force transmission mechanism 3, and the motion conversion mechanism 4, and a ventilation section 5. The ventilation section 5 includes a vent 53 penetrating a partition wall partitioning the driving force transmission mechanism 3, an air flow path 46 communicating with the vent 53, and a filter 60.

An electrically driven cylinder in which the supply of a lubricant is not needed for a long period of time. The electrically driven cylinder, comprising: a screw mechanism portion that converts rotational motion of an electric motor into linear motion; a rod that reciprocates by linear motion of the screw mechanism portion; a bushing member that regulates swinging of the rod; and a key member which is inserted into a rod groove portion provided along an axial direction of the rod and which regulates rotation of the rod; a lubricant being sealed in the screw mechanism portion, the bushing members having a plurality of holes in which a lubricant is embedded, and the key member having a plurality of holes in which a lubricant is embedded.

A good-orientation, low-drift micro-movement subassembly for angle adjustment as a precise driving screw for angle adjustment, comprising a slotted knurling handle, a turnbuckle and a central cylindrical shaft. The invention is precise for linear displacement, good orientation, low-drift, stable and reliable adjustment, which can be used for a variety of precision-oriented, small drift, precision micro-angle adjustment of the drive screw.

An apparatus for converting rotational movement into linear movement is disclosed. The apparatus comprises: a screw member having a threaded external surface and a sleeve member having a threaded interior surface for receiving the threaded external surface of the screw member, wherein the threaded surfaces are configured so that rotation of the screw member relative to the sleeve member, in use, causes the screw member to move axially relative to the sleeve member. The apparatus may also comprise a force applicator for applying pressure to the region between the screw member and sleeve member so as to urge the external surface of the screw member and the opposing interior surface of the sleeve member apart from each other.

The invention relates to an actuator (1) comprising: a body (4), a first element (5) mounted such that it can move rotatably in relation to said body (4), and a second element (6) mounted such that it can move translatably in relation to said body (4), either the first element (5) or the second element (6) being a screw and the other one being a nut, the nut cooperating with the screw such that a rotation of the first element (5) in relation to the body (4) around an axis of rotation (X) causes the translation of the second element (6) in relation to the body (4) parallel to the axis of rotation (X), a cylinder which is stationary in relation to the first element (5), a piston mounted such that it can move translatably inside the cylinder between a first end position and a second end position, and a cam surface which is stationary in relation to the body (4) and against which the piston is supported such that a rotation of the first element (5) in relation to the body (4) causes a translatory back-and-forth movement of the piston between the first end position and the second end position.

A ballscrew assembly includes a nut having a first helical groove formed on a radially inner surface and defining an axis, a screw disposed along the axis (X) and within the nut and that includes a second helical groove formed on a radially outer surface and opposed to the first helical groove so as to form a helical raceway. The assembly also includes a plurality of balls disposed in the helical raceway and an annular seal disposed radially between the nut and the screw. The seal includes a resilient body and a layer formed of PTFE and disposed radially between the resilient body and the screw and configured to contact the radially outer surface of the screw. An optional annular scraper is disposed axially adjacent to the seal and is configured to receive fluid at one axial end and expel fluid at a second axial end.