Surgical end effectors and pulley assemblies thereof

A pulley assembly for actuating a first jaw and a second jaw, the pulley assembly comprising:

• a plurality of driven pulleys, each coupled to a respective jaw and each including at least two radial sides;
• a driving pulley rotatable about a different axis from the driven pulleys;
• a plurality of cable sections, each cable section coupling different radial sides of each driven pulley to the driving pulley,
• wherein a directional change in rotation of the driving pulley relieves a tension in at least two first cable sections coupled to different radial sides of at least two of the driven pulleys and applies a tension to at least two second cable sections coupled to opposite radial sides of the driven pulleys than the first two cable sections.

An end effector of a surgical tool, the end effector comprising:

• a first jaw and a second jaw each being pivotable about a first axis;
• a first driven pulley attached to the first jaw and a second driven pulley attached to the second jaw, the first and second driven pulleys being rotatable about the first axis, each driven pulley including a first radial side and a second radial side;
• a driving pulley rotatable about a second axis;
• a first cable having a first end portion, a second end portion, and an intermediate portion, the first end portion connected to the first radial side of the first driven pulley, the second end portion connected to the second radial side of the second driven pulley, and the intermediate portion connected to the driving pulley;
• and
• a second cable having a first end portion, a second end portion, and an intermediate portion, the first end portion connected to the first radial side of the second driven pulley, the second end portion connected to the second radial side of the first driven pulley, and the intermediate portion connected to the driving pulley.