An actuator for driving a rotatable component includes a first, rotating member comprising a screw and a second member comprising a nut threaded to said screw, wherein rotation of said first member causes axial movement of said first or second member. The component also includes a third member coupled to the second member, wherein axial movement of said first or second member causes axial movement of said third member and a fourth, rotating member coupled to said third member and connectable to said component. The system also includes a bearing system located between said third member and said fourth member, said bearing system configured to cause said fourth member to rotate upon said axial movement of said third member so as to drive said component.

A brake system comprising: (a) a brake assembly including; (i) a caliper including: (1) two or more piston bores, (2) a piston located in each of the two or more piston bores, and (3) a spindle extending into each of the two or more piston bores, the spindle being rotationally movable to linearly move each of the pistons within the two or more piston bores to create a braking force; (ii) a motor gear unit in communication with each of the two or more piston bores and connected to each of the spindles extending into each of the two or more piston bores; wherein each of the spindles include threads that receive a plurality of rolling elements and when each of the spindles are rotated the two or more pistons located in each of the two or more piston bores are moved by the respective spindles to create a braking force or releasing a braking force.

Provided is an electric actuator (1), including: a motor part (A); and a motion conversion mechanism part (B). The motion conversion mechanism part (B) includes: a screw shaft (33); a nut member (32); and a planetary gear speed reducer (10) configured to reduce a speed of rotation of the rotor (24) and output the rotation. The screw shaft (33) is configured to advance toward one side in an axial direction or retreat toward another side in the axial direction in accordance with a rotation direction of the nut member (32), and the nut member (32) is arranged on an inner periphery of the rotor (24), and is coupled to a planetary gear carrier (43), which is an output member of the planetary gear speed reducer (10), so as to be capable of transmitting torque.

An electric actuator for a marine steering system comprises a housing and an output shaft reciprocatingly received by the housing. There is a rotor disposed within the housing. The rotor is coupled to the output shaft of the electric actuator. Rotation of the rotor causing the output shaft of the electric actuator to reciprocate relative to the housing. There is a motor disposed within the housing. The motor has an output shaft coupled to the rotor. A longitudinal axis of the output shaft of the motor is parallel with a longitudinal axis of the output shaft of the electric actuator. There is also a drive mechanism disposed within the housing. The drive mechanism couples the output shaft of electric actuator to the rotor. The drive mechanism is on a plane radial to a longitudinal axis of the output shaft of the motor.

The present disclosure relates to a screw drive with an element having a thread, at least one planet and a holder, wherein the at least one planet is held by the holder and rolls along the threads of the thread of the element and the holder moves linearly along the thread of the element relative to the element. The at least one planet of the screw drive is formed by a bearing which engages with its outer ring or with its inner ring in the thread of the element via an angular section.

There is disclosed a linear actuator comprising: a screw shaft comprising a screw thread and having a longitudinal axis A; a nut movable along the screw shaft from a retracted position to an extended position; and a plurality of rollers movable with the nut, each comprising a cylindrical surface configured to roll along one or more flanks of the screw thread, such that rotation of the screw shaft causes the rollers to roll along the flank(s) so that the nut translates in an axial direction along the screw shaft; wherein the screw thread comprises one or more detents (e.g., grooves) configured to lock the nut in one or more axial positions.

The present disclosure relates to the technical field of aerial work platforms, in particular to a linear actuator with a contact type safety nut, and an aerial work platform. The linear actuator includes a central screw, a driving nut mechanism, and a safety nut mechanism. The central screw has a screw raceway. The safety nut mechanism includes a safety nut seat sleeved at the periphery of the central screw. Limit hole channels pointing to the central screw are arranged on the safety nut seat. An elastic buffer element is arranged in each of the limit hole channels. A safety ball is arranged between the elastic buffer element and the central screw. The contact type safety nut enables the linear actuator to always keep safety, stability, and no loss of accuracy in a conversion process that the safety nut mechanism gets involved to take effect while the driving nut mechanism fails.

An actuator for providing a thrust force over a determined travel, comprising a nut, a screw, a sleeve configured to surround the screw in an axial direction (X-X) of the screw, a plurality of rollers, the nut being configured to cooperate with the screw, the nut being secured to the rollers, which are free to rotate, the rollers being configured to each move in particular in the one of at least one helical guide or the sleeve, the screw being configured in order, when it is turned, to operate the actuator, to rotate the nut when it bears via the rollers on a profile of the helical guide and to thus advance in the axial direction (X-X) of the screw at greater or lesser speed along a slope of the profile of the helical guide. The actuator further comprises a motor configured to turn the screw. Successive values of the slope all along the profile or profiles of respectively the one or more helical guides ae adapted to ensure that the slope systematically compensates for at least one peak of the desired thrust force in order to carry out clipping of the maximum values of the thrust force such that the motor, the screw and the nut are dimensioned to a motor torque value corresponding to the value of the thrust force after clipping.

Embodiments of an electric linear actuator may include a roller screw assembly, an electric motor coupled to the roller screw assembly, and a linear transducer operatively coupled with the roller screw assembly. The motor may be configured to drive the roller screw assembly to extend and retract another component, such as a rod. In some embodiments, the linear transducer may be configured to detect a position of the rod. The roller screw assembly may be coupled directly to the motor via a gear coupling, with the motor disposed generally in axial alignment with the roller screw assembly. Other embodiments disclosed herein include a veneer lathe carriage with electric linear actuators and corresponding apparatuses, methods, and systems.

The electromechanical actuator cylinder provides a casing, an actuation rod mounted to be movable longitudinally relative to the casing, an electric motor provided with a stator and with a rotating rotor shaft, and a mechanism for converting a rotational movement of the rotor shaft into a linear movement in translation of the actuation rod. The actuator cylinder includes at least one roller bearing for guiding the rotor shaft in rotation relative to the casing and providing at least one row of rolling elements. An inner raceway for the row of rolling elements of the bearing is formed directly on the rotor shaft.