A surgical instrument may comprise a chassis, a shaft coupled to the chassis at the proximal end of the shaft, an end effector coupled to the shaft at the distal end of the shaft, a force transmission mechanism coupled to the chassis, and an actuation element connected between a lever arm of the force transmission mechanism and the end effector. The force transmission mechanism includes a worm drive, and the lever arm comprising a first end and a follower member at the first end of the lever arm, wherein the follower member is engaged with the worm drive and is configured to be driven by the worm drive. Rotational movement of the worm drive imparts translational movement to the actuation element via the lever arm, and the lever arm slides along a generally linear direction relative to the chassis to impart the translational movement to the actuation element.

A robotic rod bender is disclosed. The robotic rod bender includes an autoclavable top assembly that includes a rod feeding subassembly, a brake subassembly, and a bending subassembly. The rod bending subassembly, the bending subassembly, and the brake assembly are disposed on a top plate. The robotic rod bender also includes a motor housing that includes one or more motors, a spline shaft, and a linear actuated elevator assembly. The linear actuated elevator assembly includes a linear actuator, a movable plate, and a mid-plate. The spine shaft extends from the moveable plate. The autoclavable top assembly is removably disposed atop the mid-plate.

A robotic rod bender is disclosed. The robotic rod bender includes an autoclavable top assembly that includes a rod feeding subassembly, a brake subassembly, and a bending subassembly. The rod bending subassembly, the bending subassembly, and the brake assembly are disposed on a top plate. The robotic rod bender also includes a motor housing that includes one or more motors, a spline shaft, and a linear actuated elevator assembly. The linear actuated elevator assembly includes a linear actuator, a movable plate, and a mid-plate. The spine shaft extends from the moveable plate. The autoclavable top assembly is removably disposed atop the mid-plate.

Embodiments of this application provide an adjustment apparatus, which includes a drive unit; a plurality of adjustment rods correspondingly connected to a plurality of loads, the plurality of adjustment rods are classified into a first adjustment rod group and a second adjustment rod group; a selection unit, where the drive unit is configured to drive the selection unit to be connected to at least one adjustment rod in the first adjustment rod group or at least one adjustment rod in the second adjustment rod group; a shift unit, where the shift unit is configured to enable the selection unit to be switched between the first adjustment rod group and the second adjustment rod group; and an adjustment unit, where the drive unit is configured to drive the adjustment unit to drive the adjustment rod connected to the selection unit to move.

Linear actuators driven by everted ball screw assemblies are described herein. In some examples, the everted ball screw assembly includes a hollow screw shaft with internal threads, a ball cylinder concentrically positioned therein and having external threads, and a plurality of balls sized to fit in a substantially contiguous series along a working pathway that is defined by the space between the internal and external threads. One or more limiters prevent the ball cylinder from rotating. A motor rotates the hollow screw shaft, thereby driving the balls along the pathway and imparting linear motion to the ball cylinder, which is coupled to a connecting rod for actuating a load. The ball cylinder in some examples includes an internal return path with scoop elements that are sized and shaped to guide the balls into the internal return path and then back onto the working pathway.

A force transmission mechanism for a surgical instrument includes a worm drive, a lever arm, and an actuation element. The lever arm may include a follower member at a first end of the lever arm. The follower member engages the worm drive and is configured to be driven by the worm drive. The actuation element is connected the lever arm. The actuation element is configured to transmit force to actuate an end effector of the surgical instrument. Rotational movement of the worm drive imparts translational movement to the actuation element via the lever arm.

A force transmission mechanism for a surgical instrument includes a worm drive, a lever arm, and an actuation element. The lever arm may include a follower member at a first end of the lever arm. The follower member engages the worm drive and is configured to be driven by the worm drive. The actuation element is connected the lever arm. The actuation element is configured to transmit force to actuate an end effector of the surgical instrument. Rotational movement of the worm drive imparts translational movement to the actuation element via the lever arm.

First and second plates have first and second elliptical apertures respectively. First and second carriage assemblies are adjacent to the first and second elliptical apertures. The first and second carriage assemblies have a common axis of rotation. First and second rails are within the first and second carriage assemblies respectively. Two first weights and two second weights are slidable along the first and second rails respectively. A first spring urges the two first weights outwardly into contact with the first elliptical aperture. A second spring urges the two second weights outwardly into contact with the second elliptical aperture. A differential mounted between the first and second plates has a first shaft rotating the first carriage assembly and first weights in a first direction. The differential has a second shaft rotating the second carriage assembly and second weights in a second direction opposite the first direction.

A ball screw having a spindle nut (21), a threaded spindle, and a retaining element (23) is provided. The retaining element (23) is connected in a form-fitting, play-free manner to the threaded nut (21) by a projection (24) which fits around the outside of the threaded nut (21) in an end region. The threaded nut (21) and the retaining element (23) functioning as a force transmission member are first positioned precisely during manufacture and then connected by a form-fitting, in particular play-free connection, in particular by caulking, crimping, clinching or other deformation processes.

A ball screw having a spindle nut (21), a threaded spindle, and a retaining element (23) is provided. The retaining element (23) is connected in a form-fitting, play-free manner to the threaded nut (21) by a projection (24) which fits around the outside of the threaded nut (21) in an end region. The threaded nut (21) and the retaining element (23) functioning as a force transmission member are first positioned precisely during manufacture and then connected by a form-fitting, in particular play-free connection, in particular by caulking, crimping, clinching or other deformation processes.