In a screw device where a shim is disposed between two nuts, a screw device that can detect preload is provided. The preload detectable screw device includes: two nuts; a shim sandwiched and compressed between the two nuts; a coupling portion configured to couple the two nuts in such a manner as to be incapable of relative rotation to each other; and a force sensor for detecting preload. A contact surface of at least one of the two nuts with the shim is provided with a recess, spaced apart from the coupling portion, in such a manner as to reduce the contact area. The force sensor is attached near the recess on an outer surface of the shim.

A motion device including a carriage for traveling along a rail. The carriage can have at least one rotatable fixed position roller, and at least one rotatable adjustable roller that is movable relative to the at least one fixed position roller for self compensating for play between the rollers and mating surfaces of the rail. Each adjustable roller can be part of a movable roller portion movably mounted to the carriage. The movable roller portion can be adjustably movable by a self adjustment mechanism. The self adjustment mechanism can include a mechanical advantage pushing member for movably engaging the movable roller portion. The mechanical advantage pushing member can be resiliently biased against the movable roller portion by a biasing arrangement. The biasing arrangement can cause movement of the mechanical advantage pushing member and the movable roller portion for moving the at least one adjustable roller for self compensating for play.

A ball screw adapted to detecting coolant liquid includes a screw, a nut, a plurality of sealing members, a sensor, a signal processing unit and a cover. The nut includes a main body and an end surface, and a through-hole and a flow channel are disposed on the main body. The nut is threadedly disposed on the screw via the through-hole. A plurality of openings are disposed on the end surface, and the openings communicate with the flow channel. The sealing members are disposed in the plurality of openings. The sensor is disposed on one of the sealing members to detect a pressure of the coolant liquid and output an original signal. The signal processing unit is electrically connected to the sensor to receive the original signal and convert the original signal to a digital signal. The cover is disposed on the sensor and fixed to the nut.

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.

A rotary actuator has a hollow motor and hollow reduction gears arranged coaxially on either side of the hollow motor. A rotary shaft is arranged so as to pass through a hollow motor shaft of the hollow motor. The hollow reduction gears have hollow input shafts connected to the shaft ends on either sides of the hollow motor shaft. The hollow reduction gears have hollow output shafts connected to sections of the rotary shaft protruding from both ends of the hollow motor shaft. The connection position of the hollow output shaft with respect to the rotary shaft can be adjusted in the rotational direction. A load is rotationally driven by the rotary shaft. By increasing the axial length of the hollow motor, it is possible to obtain a small-diameter rotary actuator having a rotational output with large torque.

A steering column device includes a male screw shaft member supported by an outer column and a female screw member provided in a link member. The female screw member and the male screw shaft member are moved relative to each other by rotation of the male screw shaft member, causing the link member to swing relative to the outer column. The female screw member includes a main body section supported by the link member, a fragile section provided on one side of the main body section, and a screw engaging section provided on the opposite side of the fragile section from the main body section. In a state where an adjust nut is screwed to the screw engaging section, a distal end portion of the adjust nut comes into contact with the main body section and extends the fragile section in the axial direction of the male screw shaft member.

A linear motion system includes a guiding member, a moving member, a plurality of rolling members, a controller, a preload sensing member and a preload adjusting module. The moving member is slidably disposed on the guiding member, and the moving member and the guiding member together form a circulation path. The rolling members are accommodated in the circulation path. The preload sensing member is disposed on the moving member. The preload sensing member detects a preload value generated by the rolling members and applied to the moving member, and outputs a detecting signal to the controller. The preload driver and adjusting assembly of the preload adjusting module are disposed on the moving member. The controller controls the preload driver to adjust the adjusting assembly according to the detecting signal to adjust the preload value to a preset value.

A linear motion system comprises a guiding member, a moving member, a plurality of rolling members and a preload adjusting module. The moving member is slidably disposed on the guiding member. The moving member and the guiding member together form a circulation path. When the guiding member moves with relative to the moving member, the moving member can generate a linear movement with relative to the guiding member. The rolling members are accommodated in the circulation path. The preload adjusting module is disposed on the moving member, and comprises a preload assembly and a preload regulator. The preload regulator applies a thrust to the preload assembly to adjust a preload value generated by the rolling members and applied to the moving member.

An anti-backlash nut for engaging a threaded screw includes an anti-backlash nut body extended along a longitudinal axis configured and adapted to receive a screw, the anti-backlash nut body including a first threaded section having a first inner diameter with a first internal thread and a second threaded section integral to the first threaded section having a second internal thread, where the first thread and the second thread have an equal pitch and are out-of-phase with respect with each other.

A system comprises a drive system comprising a single motor, a transmission configured to transmit power from the single motor to a first ball screw via a first clutch, and a second clutch configured to transmit power from the first ball screw to a second ball screw. The system also comprises a brake configured to apply a braking force to at least a portion of the drive system. The system further comprises a control module configured to control operation of one or more of the single motor, the first clutch, the second clutch, and the brake, where the control module is configured to move a scissors arms in a horizontal direction in a first configuration and adjust a vertical height of the scissors arms in a second configuration.