Manufacturing electrosurgical instruments

1. A method for manufacturing a jaw member for an electrosurgical instrument, comprising the steps of:

providing a jaw housing having a longitudinal jaw section;

providing an electrically conductive plate including one or more passages that extend through a thickness direction of the electrically conductive plate;

disposing the electrically conductive plate on the jaw section of the jaw housing;

placing the jaw housing and the electrically conductive plate into a mould;

injecting a flowable insulating material into the mould to secure the electrically conductive plate to the jaw housing, such that the flowable material flows through the one or more passages to form one or more stop members that project a predetermined distance from the electrically conductive plate;

allowing the flowable insulating material to solidify; and

removing the jaw housing, electrically conductive plate and the solidified insulating material from the mould as a jaw member,

wherein the mould comprises volumes located above the one or more passages when the jaw housing and plate are located in the mould, the volumes permitting the flowable insulating material to flow thereinto to form the stop members.

2. A method according to claim 1 , wherein the injecting step is such that the predetermined distance is about 20 μu to about 350 μm (0.00079 inches to about 0.014 inches).

3. A method according to claim 1 , including the step of providing a pre-moulded insert that can be received within the jaw housing.

4. A method according to claim 3 , wherein the step of disposing the electrically conductive plate on the jaw section of the jaw housing comprises inserting the pre-moulded insert into the jaw housing, and then placing the electrically conductive plate on to the insert.

5. A method according to claim 1 , including the additional step of disposing an electrically conductive lead against the conductive plate before the flowable insulating material is injected into the mould.

6. A method according to claim 5 , wherein the flowable insulating material secures the lead in electrical connection with the conductive plate.

7. A method according to claim 1 , wherein the conductive plate includes a plurality of passages therethrough.

8. A method according to claim 7 , wherein the plurality of passages are disposed along the longitudinal axis of the conductive plate.

9. A method according to claim 1 , wherein the one or more passages are through holes.

10. A method according to claim 1 , wherein the one or more passages are cut-outs.

11. A method according to claim 1 , wherein the mould abuts against the electrically conductive plate when the plate is placed into the mould in regions other than where the volumes are provided whereby to prevent the flowable insulating material from encroaching onto an upper surface of the electrically conductive plate.

12. A method for manufacturing a jaw member for an electrosurgical instrument, comprising the steps of:

providing a jaw housing having a longitudinal jaw section;

providing an electrically conductive plate including one or more passages that extend through a thickness direction of the electrically conductive plate;

disposing the electrically conductive plate on the jaw section of the jaw housing;

placing the jaw housing and the electrically conductive plate into a mould;

injecting a flowable insulating material into the mould to secure the electrically conductive plate to the jaw housing, such that the flowable material flows through the one or more passages to form one or more stop members that project a predetermined distance from the electrically conductive plate;

allowing the flowable insulating material to solidify; and

removing the jaw housing, electrically conductive plate and the solidified insulating material from the mould as a jaw member, wherein:

the electrically conductive plate includes a longitudinally extending slot configured to receive a translatable knife blade;

the passages are disposed adjacent the longitudinally extending slot; and

the mould comprises volumes located above the one or more passages when the jaw housing and plate are located in the mould, the volumes permitting the flowable insulating material to flow thereinto to form the stop members.

13. A method according to claim 12 , wherein the passages contact either side of the longitudinally extending slot.

14. A jaw member for an electrosurgical instrument manufactured by the following steps:

i) providing a jaw housing having a longitudinal jaw section;

ii) providing an electrically conductive plate including one or more passages that extend through a thickness direction of the electrically conductive plate;

iii) disposing the electrically conductive plate on the jaw section of the jaw housing;

iv) placing the jaw housing and the electrically conductive plate into a mould;

v) injecting a flowable insulating material into the mould to secure the electrically conductive plate to the jaw housing, such that the flowable material flows through the one or more passages to form one or more stop members that project a predetermined distance from the electrically conductive plate;

vi) allowing the flowable insulating material to solidify; and

vii) removing the jaw housing, electrically conductive plate and the solidified insulating material from the mould as a jaw member,

wherein the mould comprises volumes located above the one or more passages when the jaw housing and plate are located in the mould, the volumes permitting the flowable insulating material to flow thereinto to form the stop members.