Patent ID: 7357287

Claim:
A surgical instrument, comprising: a handle; an elongate implement portion extending distally from said handle and further comprising at least one deformable fastener member adjacent to a distal end of the elongate implement portion; a firing mechanism for deforming the at least one deformable fastener member to securely attach the at least one deformable fastener member to tissue, comprising: a distal portion received for longitudinal reciprocating motion in the elongate implement portion, and a proximal portion received in the handle for reciprocating movement between an unfired position and a fired position and coupled to the distal portion to transfer the related longitudinal reciprocating motion; a firing actuator movably attached to the handle and coupled to move the proximal portion of the firing mechanism from the unfired position to the fired position to attach the at least one deformable fastener member to tissue; and an assistance mechanism, comprising: a follower member received in the handle, proximate and aligned for movement between the unfired and fired positions of the proximal portion of the firing mechanism, a biasing member operatively configured to urge the follower member in a selected direction between unfired and fired positions and to be preloaded by movement of the follower member in an opposing direction, and an engagement mechanism operatively configured, in response to the proximal portion of the firing mechanism beginning movement in the selected direction, to engage the preloaded follower member to the proximal portion of the firing mechanism, wherein the preload assistance mechanism urges the firing mechanism in the selected direction during reciprocation of the firing mechanism to deformably attach the at least one deformable fastener to tissue.