Forceps with spring loaded end effector assembly

1. An endoscopic forceps for treating tissue, comprising:

a handle assembly having a elongated shaft extending therefrom, the shaft being movable relative to the handle assembly by an actuator;

an end effector assembly attached to a distal end of the shaft, the end effector assembly having first and second jaw members being movable about a pivot from a first position in spaced relation relative to one another to a second position for clamping tissue, a tissue-contacting surface of the first jaw defining a longitudinal plane when the first jaw member is in the second position, each of the jaw members including:

a housing having an electrically conductive, inwardly facing tissue contacting surface;

a flange having at least one camming surface, the flange including a spring-like tail which mounts at least partially within the distal end of the elongated shaft to bias the jaw members in an open configuration, wherein portions of the spring-like tail are on opposite sides of the longitudinal plane when the jaw members are in the open configuration, wherein a proximal portion of the spring-like tail is biased radially outward within the distal end of the elongated shaft;

the actuator being movable relative to the handle to actuate the elongated shaft from a first position wherein the elongated shaft remains proximal to the flanges of the jaw members and the jaw members are biased in an open configuration to at least one subsequent position wherein the distal end of the elongated shaft cams the flanges to pivot the jaw members toward the second position to clamp tissue.

2. An endoscopic forceps according to claim 1 , wherein the flanges of the jaw members cooperate with the distal end of the elongated shaft to provide a clamping pressure within the range of at least about 3 kg/cm 2 to effectively seal tissue upon application of electro surgical energy.

3. An endoscopic forceps according to claim 2 , wherein the flanges of the jaw members include sloped forward surfaces which cooperate with the distal end of the elongated shaft to maintain the jaw members in the second position.

4. An endoscopic forceps according to claim 3 , wherein once the distal end of the elongated shaft translates over the forward surfaces of the flanges, clamping pressure is maintained within the range of at least about 3 kg/cm 2 .

5. An endoscopic forceps for treating tissue, comprising:

a handle assembly having a elongated shaft extending therefrom, the shaft being movable relative to the handle assembly by an actuator;

an end effector assembly attached to a distal end of the shaft, the end effector assembly having first and second jaw members being movable about a pivot from a first position in spaced relation relative to one another to a second position for clamping tissue;

a knife actuator for advancing a knife through tissue held between jaw members;

wherein each of the jaw members includes:

a housing having an electrically conductive, inwardly facing tissue contacting surface;

a flange having at least one camming surface, the flange including a spring-like tail which mounts at least partially within the distal end of the elongated shaft to bias the jaw members in an open configuration, wherein portions of the spring-like tail are on opposite sides of the longitudinal plane when the jaw members are in the open configuration, wherein a proximal portion of the spring-like tail is biased radially outward within the distal end of the elongated shaft;

a knife channel for reciprocating the knife therethrough;

the actuator being movable relative to the handle to actuate the elongated shaft from a first position wherein the elongated shaft remains proximal to the flanges of the jaw members and the jaw members are biased in an open configuration to at least one subsequent position wherein the distal end of the elongated shaft cams the flanges to pivot the jaw members toward the second position to clamp tissue.