US 12,408,902 B2
Drive patterns and spline arrangement for robotic surgical tools
Andrew T. Beckman, Cincinnati, OH (US); and Charles J. Scheib, Loveland, OH (US)
Assigned to Cilag GmbH International, Zug (CH)
Filed by Cilag GmbH International, Zug (CH)
Filed on Jun. 22, 2020, as Appl. No. 16/946,430.
Prior Publication US 2021/0393346 A1, Dec. 23, 2021
Int. Cl. A61B 17/00 (2006.01); B25J 19/06 (2006.01)
CPC A61B 17/00 (2013.01) [B25J 19/068 (2013.01)] 18 Claims
OG exemplary drawing
 
7. A surgical tool, comprising:
a handle having a shroud, a first end defining a central aperture, and a second end, the shroud extending from the first end to the second end;
a lead screw disposed within the handle and rotatably coupled to the handle and extending between the first and second ends of the handle;
first and second splines disposed in the handle and rotatably coupled to the handle, the first and second splines extending between the first and second ends of the handle;
a carriage disposed in the handle and movably mounted to the lead screw via a carriage nut supported by the carriage and arranged about the lead screw, the carriage being translatable between the first and second ends as the lead screw rotates, wherein the carriage comprises first, second, and third layers removably secured to each other in series, the first layer being located closer to the first end of the handle than the second layer, the third layer interposing the first and second layers, and wherein the carriage nut is partially disposed in the first and third layers;
an elongate shaft extending through the central aperture and having a longitudinal axis that is coaxial with a longitudinal axis of the handle, a first shaft end of the elongate shaft being disposed in the handle and directly coupled to and extending from the carriage, wherein the elongate shaft translates along the longitudinal axis of the handle as the carriage translates, and wherein the first and second splines and the lead screw are radially arranged about the elongate shaft;
an end effector being operatively coupled to a second shaft end of the elongate shaft;
a first activating mechanism supported by the carriage and operatively coupled to the first spline so that rotation of the first spline operates the first activating mechanism and thereby causes the end effector to actuate in a first operation;
a second activating mechanism supported by the carriage and operatively coupled to the second spline so that rotation of the second spline operates the second activating mechanism and thereby causes the end effector to actuate in a second operation;
wherein rotating the first spline in a first direction to actuate the end effector in the first operation generates a first torsional load, and rotating the second spline in a second direction opposite the first direction to actuate the end effector in the second operation generates a second torsional load, and
wherein the first torsional load is balanced by the second torsional load.