Surgical instrument actuator with non-collinear hydraulic pistons

Claim 1

In a hand-operated surgical instrument for implanting a fastener in tissue to close a wound in the tissue, said instrument having at least one movable operating member for implanting the fastener in tissue, said operating member being disposed remote from or extending from a movable handle means for actuating said member, the improvement characterized in that a hydraulic actuating means is operably connected between said handle means and said operating member for effecting the movement of said operating member to implant said fastener when said handle means is moved relative to said instrument, said actuating means comprising: first and second connected chambers rigidly disposed in said instrument, each said chamber having a generally cylindrical configuration and said second chamber being oriented with its longitudinal axis at an angle relative to the longitudinal axis of said first chamber; first and second pistons slidably disposed in said first and second chambers respectively; a substantially incompressible fluid occupying the volume within said connected first and second chambers between said first and second pistons; means connecting said operating member with said first piston; caming means associated with said handle means and cam follower means connected with said second piston for engaging said camming means and being moved by said handle means to force said second piston along said second chamber thereby forcing said fluid from said second chamber into said first chamber to move said first piston from a first piston to a second piston to effect said movement of the connected operating member; and first piston biasing means for biasing said first piston from said second position to said first position.