Surgical stapling apparatus

1. A surgical apparatus comprising:

a handle assembly;

an elongated body extending distally from the handle assembly and defining a longitudinal axis;

a tool assembly supported at the distal end of the elongated body and being pivotable about a pivot axis with respect to the elongated body, the tool assembly including an anvil assembly and a cartridge assembly having a plurality of surgical staples;

a flexible drive member extending from a position proximal of the pivot axis to a position distal of the pivot axis, the drive member having a distal end which is movable in relation to the tool assembly to actuate the tool assembly, the drive member being configured as a beam; and

a blow out member having a proximal end positioned on one side of the drive member and extending from a position proximal of the pivot axis to a position distal of the pivot axis, the blow out member having a planar surface adjacent to the pivot axis such that the at least one blow-out member is positioned to inhibit outward bulging of the flexible drive member.

2. A surgical apparatus according to claim 1 , further comprising a second blow out member positioned on an opposite side of the flexible drive member.

3. A surgical apparatus according to claim 1 , further comprising a mounting assembly for pivotally mounting the tool assembly.

4. A surgical apparatus according to claim 3 , wherein the tool assembly is fixedly secured to the mounting assembly and the mounting assembly is pivotally secured at the distal end of the elongated body.

5. A surgical apparatus according to claim 1 , wherein the flexible drive member includes at least one flat sheet of material.

6. A surgical apparatus according to claim 5 , wherein the flexible drive member includes a plurality of sheets of material.

7. A surgical apparatus according to claim 1 , wherein the flexible drive member includes a distal working head for actuating the tool assembly.

8. A surgical apparatus according to claim 7 , wherein the distal working head of the flexible drive member includes a cam member positioned to engage the anvil assembly.

9. A surgical apparatus according to claim 8 , wherein the distal working head of the flexible drive member supports an engagement member positioned for slidable movement along an exterior surface of the cartridge assembly.

10. A surgical apparatus according to claim 1 , wherein the distal working head includes vertical strut and a knife blade.

11. A surgical apparatus according to claim 1 , wherein the anvil assembly is movable in relation to the cartridge assembly between open and clamped positions.

12. A surgical stapling apparatus comprising:

a handle assembly;

an elongated body extending distally from the handle assembly and defining a longitudinal axis;

a tool assembly supported adjacent a distal end of the elongated body and being pivotable with respect to the elongated body, the tool assembly including an anvil assembly and a cartridge assembly having a plurality of surgical staples;

a flexible drive member extending from a position proximal of the pivot axis to a position distal of the pivot axis, the drive member having a distal end which is movable in relation to the tool assembly to actuate the tool assembly, the drive member being configured as a beam having a plurality of stacked sheets; and

an actuation shaft mounted for longitudinal movement in response to manipulation of the handle, the actuation shaft being arranged to move the drive member longitudinally in relation to the tool assembly.

13. A surgical stapling apparatus according to claim 12 , further comprising an articulation mechanism mounted adjacent the handle assembly.

14. A surgical stapling apparatus according to claim 13 , wherein the articulation mechanism has an articulation link extending through the elongated body.

15. A surgical stapling apparatus according to claim 12 , wherein the anvil member has a longitudinal slot to facilitate passage of the drive member.

16. A surgical stapling apparatus according to claim 15 , wherein the drive member has a knife blade.

17. A surgical stapling apparatus according to claim 15 , wherein the tool assembly includes a staple cartridge having a longitudinal slot for facilitating passage of the drive member.

18. A surgical stapling apparatus according to claim 12 , further comprising a mounting assembly for mounting the tool assembly for articulation.

19. A surgical stapling apparatus according to claim 18 , wherein the mounting assembly has a pivot member.

20. A surgical stapling apparatus according to claim 12 , wherein the drive member includes a proximal engagement section having engagement fingers.

21. A surgical stapling apparatus according to claim 20 , wherein a distal end of the drive member defines a support strut.

22. A surgical stapling apparatus according to claim 21 , wherein the strut includes a flange that projects distally.

23. A surgical stapling apparatus according to claim 22 , wherein the flange supports a cam roller.

24. A surgical stapling apparatus according to claim 12 , wherein each sheet abuts at least one other adjacent sheet along the entire length of the stacked sheets.

25. A surgical stapling apparatus according to claim 12 , wherein the handle assembly includes a movable handle and the movable handle must be moved more than once to eject all of the surgical staples from the tool assembly.

26. A surgical stapling apparatus according to claim 25 , wherein the movable handle is pivotably supported.

27. A surgical stapling apparatus according to claim 12 , wherein the tool assembly has linear rows of the staples having a length of about 60 mm.