Surgical fastener applying apparatus

1. A surgical fastener applying apparatus comprising:

an anvil half-section including a distal anvil portion and a proximal handle portion;

a cartridge receiving half-section defining an elongated channel member, the elongated channel member having a distal portion dimensioned to releasably receive a single use loading unit and a proximal portion configured to support a firing assembly,

a clamping lever secured to the cartridge receiving half-section, the clamping lever having a proximal portion and a distal portion and including a handle portion supporting an engagement member; and

a firing assembly configured to be releasably supported within the proximal portion of the cartridge receiving half-section and including a stationary housing releasably received within the proximal portion of the cartridge receiving half section, a firing lever, a cam bar fixedly secured to the firing lever, and a pivotal locking member including a latch portion, the pivotal locking member being pivotally supported on a proximal end of the stationary housing;

the clamping lever being operably associated with the anvil half-section and the cartridge receiving half-section and being movable from an unclamped position to a clamped position to releasably secure the anvil portion of the anvil half-section in close approximation with the single use loading unit, wherein in the clamped position, the engagement member of the clamping lever releasably engages the latch portion of the locking member to releasably retain the clamping lever in the clamped position.

2. The surgical fastener applying apparatus according to claim 1 , wherein the engagement member includes a cylindrical post.

3. The surgical fastener applying apparatus according to claim 1 , wherein the locking member includes a pair of pivot members which are pivotally supported in openings defined in a proximal end of the stationary housing of the firing assembly.

4. The surgical fastener applying apparatus according to claim 2 , wherein the latch portion includes a hook member engageable with the engagement member of the clamping lever.

5. The surgical fastener applying apparatus according to claim 1 , further comprising a finger engagement member positioned on the locking member, wherein the finger engagement member is depressed to release the latch portion from the engagement member of the clamping lever.

6. The surgical fastener applying apparatus according to claim 5 , wherein the finger engagement member is positioned proximal of the firing lever.

7. The surgical fastener applying apparatus according to claim 5 , wherein the finger engagement member is positioned on one end of the locking member and the latch portion is positioned on the other end of the locking member.

8. The surgical fastener applying apparatus according to claim 3 , wherein the elongated channel member has first and second cutouts to receive the pivot members to releasably secure the firing assembly within the proximal portion of the channel member.

9. The surgical fastener applying apparatus according to claim 8 , wherein the cutouts are partially defined by fingers.

10. The surgical fastener applying apparatus according to claim 1 , wherein the firing assembly and single use loading unit are disposable and the anvil half-section, cartridge receiving half-section and clamping lever are reusable.

11. The surgical fastener applying apparatus according to claim 1 , further comprising a biasing member urging the latch portion inwardly towards the stationary housing.

12. The surgical fastener applying apparatus according to claim 1 , wherein the latch portion extends through an opening in the proximal end of the stationary housing and below a bottom surface of the elongate channel member.

13. The surgical fastener applying apparatus according to claim 1 , further including a spring member which is supported on the clamping lever and positioned to engage the cartridge receiving half-section to urge the clamping lever to the unclamped position.

14. The surgical fastener applying apparatus according to claim 3 , wherein the stationary housing includes a U-shaped frame including a bottom wall and a pair of sidewalls, each of the sidewalls having a proximal end defining the openings, the pivot members extending through the openings at a position to be received in cutouts in a proximal end of the cartridge receiving half-section to releasably retain the stationary housing within the proximal portion of the elongated channel member.

15. The surgical fastener applying apparatus according to claim 1 , wherein the firing assembly further includes a knife actuating bar which is configured to engage a knife supported within the single use loading unit.

16. The surgical fastener applying apparatus according to claim 1 , wherein the firing assembly further includes a guide block axially fixed within the U-shaped frame and a slide block slidably positioned with the U-shaped frame, wherein the firing lever is pivotally secured to the slide block and the cam bar is fixedly secured to the slide block, the slide block being slidable through the U-shaped frame to advance the cam bar through the distal portion of the elongated channel member.

17. The surgical fastener applying apparatus according to claim 1 , wherein the cartridge receiving half-section includes a sidewall defining a depression and the clamping lever includes a sidewall defining a protrusion, the protrusion being positionable within the depression to retain the clamping lever.

18. The surgical fastener applying apparatus according to claim 17 , wherein the clamping lever is releasably secured to the cartridge receiving half-section, the clamping lever movable to move the protrusion out of engagement within the depression to enable detachment of the clamping lever from the cartridge receiving half-section.