Surgical instrument with an anvil that is selectively movable about a discrete non-movable axis relative to a staple cartridge

1. A surgical instrument, comprising:

an elongate channel configured to operably support a surgical staple cartridge therein;

an anvil pivotally coupled to a proximal end of the elongate channel, the anvil being pivotable about a discrete, non-movable anvil axis defined by said elongate channel;

a firing member configured for axial travel within the elongate channel in response to an application of firing motions thereto, the firing member being configured to movably engage the anvil and the elongate channel to space the anvil relative to the elongate channel at a desired spacing as the firing member is axially driven through the elongate channel; and

a closure member configured to move the anvil between an open position and closed positions relative to the elongate channel upon application of closure motions to the closure member.

2. The surgical instrument of claim 1 wherein said elongate channel is coupled to an elongate shaft assembly, the elongate shaft assembly defining a shaft axis and wherein said closure member is axially movable between an unactuated position and an actuated position along the shaft axis.

3. The surgical instrument of claim 2 wherein said elongate shaft assembly comprises a frame assembly coupled to the elongate channel and wherein the closure member is axially movable relative to the frame assembly.

4. The surgical instrument of claim 1 wherein said anvil comprises:

an anvil body including a staple forming undersurface; and

an anvil mounting portion comprising:

a proximally protruding first anvil arm including an inwardly extending first anvil trunnion; and

a proximally protruding second anvil arm spaced from the first anvil arm and including an inwardly extending second anvil trunnion spaced from the first anvil trunnion, said first anvil trunnion pivotally supported in a first trunnion hole in a first proximal end portion of the elongate channel and the second anvil trunnion pivotally supported in a second trunnion hole in a second proximal end portion of the elongate channel, the first and second trunnion holes coaxially aligned with each other on the anvil axis.

5. The surgical instrument of claim 4 wherein said anvil further comprises an anvil ramp configured for contact with a distal end of the closure member.

6. The surgical instrument of claim 1 wherein said anvil further comprises:

a staple forming undersurface;

a firing member slot in the staple forming undersurface;

a first closure ledge in the anvil adjacent a first side of the firing member slot;

a second closure ledge in the anvil adjacent a second side of the firing member slot;

a channel slot extending through a bottom of the elongate channel and wherein said firing member comprises:

a vertically extending firing member body;

a first firing member tab protruding from a first lateral side of the vertically extending firing member body to be slidably received on said first closure ledge in the anvil;

a second firing member tab protruding from a second lateral side of the vertically extending firing member body to be slidably received on said first closure ledge in the anvil; and

a bottom foot portion on a bottom end of the vertically extending firing member body and extending laterally from said first and second lateral sides of the vertically extending firing member body.

7. The surgical instrument of claim 6 further comprising:

a first closure ledge ramp communicating with the first closure ledge on a proximal end thereof, the first closure ledge ramp configured to guide the first firing member tab onto the first closure ledge upon the application of the firing motions to the firing member; and

a second closure ledge ramp communicating with the second closure ledge on a proximal end thereof, the second closure ledge ramp configured to guide the second firing member tab onto the second closure ledge upon the application of the firing motions to the firing member.

8. The surgical instrument of claim 6 wherein the vertically extending firing member body comprises a tissue cutting surface.

9. The surgical instrument of claim 1 further comprising:

an elongate shaft assembly operably coupled to the elongate channel; and

a housing operably coupled to the elongate shaft assembly and operably supporting a firing system configured to generate the firing motions and a closure system configured to generate the closure motions.

10. The surgical instrument of claim 9 wherein the housing comprises a handle.

11. The surgical instrument of claim 10 wherein at least one of said firing system and said closure system is manually operable.

12. The surgical instrument of claim 10 wherein at least one of said firing system and said closure system is motor powered.

13. The surgical instrument of claim 9 wherein the housing comprises a portion of a robotic system.

14. The surgical instrument of claim 9 wherein said elongate channel is pivotally coupled to said elongate shaft assembly such that said elongate channel may be selectively articulated about an articulation axis that is transverse to a shaft axis defined by said elongate shaft assembly.

15. The surgical instrument of claim 14 further comprising an articulation assembly operably coupled to the elongate channel, the articulation assembly being responsive to articulation motions generated by an articulation system.

16. A surgical instrument, comprising:

an elongate channel;

a surgical staple cartridge operably supported in said elongate channel, the surgical staple cartridge operably supporting a plurality of surgical staples therein;

a firing member operably supported for axial travel through the surgical staple cartridge to eject the surgical staples from the surgical staple cartridge;

an anvil including an anvil forming surface configured to form the surgical staples ejected from the surgical staple cartridge, wherein the firing member is configured to movably engage the anvil and the elongate channel to space the anvil relative to the elongate channel at a desired spacing as the firing member is axially driven through the elongate channel;

means for moving the firing member through the surgical staple cartridge;

means for mounting a proximal end of the anvil to the elongate channel such that the anvil is selectively pivotable relative to the elongate channel without the proximal end of the anvil moving relative to the elongate channel; and

means for pivoting a distal end of the anvil toward the elongate channel, the means for pivoting being independently operable from the means for moving the firing member.

17. The surgical instrument of claim 16 wherein said means for moving is unactuatable until said means for pivoting has pivoted the distal end of the anvil to a closed position.