Tensioning Mechanism for Articulation Drive Cables

A surgical instrument, comprising:

• a housing;
• an elongated shaft extending distally from the housing, the elongated shaft including a proximal portion defining a longitudinal axis and a distal articulating portion pivotable with respect to the proximal portion;
• an end effector for treating tissue supported by the elongated shaft;
• an articulation drive mechanism operable to pivot the distal articulating portion of the elongated shaft, the articulation drive mechanism including at least one tensile member extending at least partially through the elongated shaft and configured to induce the distal articulating portion of the elongated shaft to pivot;
• and
• a tensioning mechanism configured to impart a variable force to the at least one tensile member to maintain the at least one tensile member in tensile state, the variable force dependent upon a variable length of the at least one tensile member.

A surgical instrument, comprising;

• a housing;
• an elongated shaft extending distally from the housing;
• an end effector extending distally from the elongated shaft, the end effector for treating tissue;
• at least one tensile member extending at least partially through the elongated shaft, the at least one tensile member operable from an actuator supported by the housing to induce movement of the end effector;
• and
• a spring operatively coupled to the at least one tensile member to impart a tensile force thereto.