Surgical instrument

A disposable surgical instrument comprising:

• a handle;
• a rigid stem section extending from said handle and defining a longitudinal axis of said surgical instrument;
• a flexible stem section extending from a distal end of said rigid stem section;
• a surgical tool connected with a distal end of said flexible stem section, said surgical tool including a fixed part fixed for movement with said distal end of said flexible stem section, said surgical tool including a movable part supported for pivotal movement relative to said fixed part about a pivot axis;
• and
• said movable part of said surgical tool having a main body portion engageable with said fixed part and having a moment arm fixed to and movable with said main body portion, said moment arm extending generally perpendicular to said main body portion;
• a flexible actuator cable having a first end portion movable by an actuator member on said handle, an intermediate portion extending through said flexible stem section, and a second end portion extending around a curved surface on said moment arm and connected with said movable part;
• said actuator cable transmitting force from said actuator member to said moment arm of said movable part along a line of action extending between said curved surface on said moment arm and said flexible stem section to effect pivotal movement of said movable part about said pivot axis;
• said actuator cable extending tangentially from said curved surface on said moment arm, and said actuator cable applying force to said moment arm of said movable part where said actuator cable extends around said curved surface on said moment arm, whereby the perpendicular distance from said pivot axis to the line of action of the force applied by said actuator cable increases as said movable part pivots from an open position to a closed position relative to said fixed part.