Surgical instrument having a plastic surface

1. A surgical instrument, comprising:

a handle portion;

a body portion extending distally from the handle portion and defining a first longitudinal axis;

a movable handle disposed on the handle portion and in mechanical cooperation with a drive member;

a tool assembly including an anvil and a cartridge assembly and a portion of the tool assembly defining a first contact surface and another portion of the tool assembly defining a second contact surface, the first contact surface and the second contact surface being at least partially formed of metal, the tool assembly being supported adjacent a distal end of the body portion;

a drive beam having a proximal engagement portion disposed adjacent a proximal end thereof and being configured to engage a portion of the drive member;

a closure apparatus disposed adjacent a distal end of the drive beam being configured to engage the first contact surface and the second contact surface of the tool assembly, whereby at least a partial actuation of the movable handle moves the closure apparatus distally so that a first portion of the closure apparatus moves into engagement with the first contact surface and a second portion of the closure apparatus moves into engagement with the second contact surface to approximate the anvil and the cartridge assembly, the closure apparatus being formed of metal, and at least the first portion and the second portion of the closure apparatus each including a plastic overmold, wherein the plastic overmolds included on the first and second portions of the closure apparatus minimize friction between the first and second portions of the closure apparatus and the first and second contact surfaces of the tool assembly.

2. The surgical instrument of claim 1 , wherein the plastic overmolds are configured as caps at least partially covering the first portion and the second portion of the closure apparatus.

3. The surgical instrument of claim 2 , wherein the caps are configured and dimensioned to at least partially cover horizontal surfaces of the closure apparatus.

4. The surgical instrument of claim 1 , wherein the closure apparatus includes a cutting surface thereon.

5. The surgical instrument of claim 1 , wherein at least a portion of the first contact surface and at least a portion of the second contact surface of the tool assembly include a plastic surface thereon.

6. The surgical instrument of claim 1 , wherein the drive beam includes a plurality of layers.

7. The surgical instrument of claim 1 , wherein the closure apparatus is part of a disposable loading unit.

8. The surgical instrument of claim 1 , wherein the tool assembly defines a second longitudinal axis, the tool assembly being movable from a first position in which the second longitudinal axis is substantially aligned with the first longitudinal axis to a second position in which the second longitudinal axis is disposed at an angle to the first longitudinal axis.

9. The surgical instrument of claim 1 , wherein the closure apparatus includes an I-shaped cross section.

10. A surgical instrument, comprising:

a handle portion;

a body portion extending distally from the handle portion and defining a first longitudinal axis;

a movable handle disposed on the handle portion and in mechanical cooperation with a drive member;

a tool assembly supported adjacent a distal end of the body portion, the tool assembly including an anvil and a cartridge assembly pivotally connected for movement between open and closed positions, the anvil defining a first contact surface and the cartridge assembly defining a second contact surface, the first and second contact surfaces being formed from metal;

a drive beam having a proximal engagement portion disposed adjacent a proximal end thereof and being configured to engage a portion of the drive member; and

a closure apparatus disposed adjacent a distal end of the drive beam, the closure apparatus including an upper portion configured and dimensioned to engage the anvil and a lower portion configured and dimensioned to engage the cartridge assembly such that actuation of the movable handle moves the closure apparatus from a retracted position to an advanced position to move the anvil and the cartridge assembly from the open position to the closed position, the closure apparatus further including a first cap member formed from plastic and positioned between the upper portion and the anvil to reduce friction therebetween during movement of the closure apparatus from the retracted position to the advanced position, and a second cap member formed from plastic and positioned between the lower portion and the cartridge assembly to reduce friction therebetween during movement of the closure apparatus from the retracted position to the advanced position and thereby facilitate a reduction in firing force.

11. The surgical instrument of claim 10 , wherein the upper and lower portions of the closure apparatus are connected by an intermediate portion positioned therebetween, the upper and lower portions extending outwardly of the intermediate portion such that the upper portion defines an upper horizontal portion and the lower portion defines a lower horizontal portion.

12. The surgical instrument of claim 11 , wherein the first cap member covers the upper horizontal portion and the second cap member covers the lower horizontal portion.

13. The surgical instrument of claim 11 , wherein the first cap member includes a first reinforced section configured and dimensioned for engagement with the intermediate portion of the closure apparatus, and the second cap member includes a second reinforced section configured and dimensioned for engagement with the intermediate portion of the closure apparatus, whereby the first and second reinforced sections increase minimize relative movement between the first cap member and the upper portion of the closure apparatus and relative movement between the second cap member and the lower portion of the closure apparatus.

14. The surgical instrument of claim 11 , wherein the intermediate portion includes a cutting surface.

15. The surgical instrument of claim 10 , wherein the first cap member is removably connected to the upper portion of the closure apparatus, and the lower cap member is removably connected to the lower portion of the closure apparatus.