A surgical instrument is provided comprising: a first jaw having a distal end and a proximal end wherein the proximal end of the first jaw is attached to a lever arm that includes a levering cam slot having a proximal portion and a distal portion； a second jaw having a distal end and a proximal end wherein the proximal end of the second jaw is secured to a base that includes a linear cam slot aligned with a longitudinal axis of the second jaw axis and having a proximal portion and a distal portion； a pivot rotatably mounting the first jaw to the second jaw, wherein a pivot axis extends between the first jaw and the lever arm； a cam pin configured to extend through and engage the levering cam slot and the linear cam slot； a linear drive member operatively coupled to drive the cam pin to follow the linear cam slot； wherein the cam pin imparts a lever force upon the lever arm that rotates the first jaw way from the second jaw when the cam pin contacts the distal portion of the levering cam slot and wherein the cam pin imparts a lever force upon the lever arm that rotates the first jaw toward the second jaw when the cam pin contacts the proximal end portion of the levering cam slot
