Abstract: A robotic surgical tool includes a drive housing having first and second ends, a spline extending between the ends and including a drive gear that rotates with spline rotation, and a carriage mounted to the spline. A shaft extends from the carriage, penetrates the first end, and has an end effector arranged at a distal end. An activating mechanism is housed in the carriage and includes an input gear operatively coupled to the drive gear such that rotation of the drive gear correspondingly rotates the input gear, and a firing rod defining external threads threadably engageable with internal threads of the input gear. The firing rod is coupled to a knife at the end effector such that movement of the firing rod correspondingly moves the knife in the same direction. The drive gear is rotated to rotate the input gear and thereby move the firing rod and the knife.

Abstract: A robotic surgical tool includes a drive housing having first and second ends, at least one spline extending between the first and second ends and including a drive gear that rotates with rotation of the spline, and a carriage mounted to the spline. A closure tube extends from the carriage through the first end and has an end effector arranged at a distal end. An activating mechanism is housed in the carriage and includes a driven gear coupled to the drive gear such that rotation of the drive gear rotates the driven gear, and a carrier arranged at a proximal end of the closure tube and coupled to the driven gear such that rotation of the driven gear moves the carrier and the closure tube axially along a longitudinal axis of the closure tube. Moving the closure tube along the longitudinal axis closes or opens end effector jaws.