MANUFACTURING ELECTROSURGICAL INSTRUMENTS

Abstract

A pair of jaw members for an electrosurgical instrument is manufactured by providing first and second jaw members (2 & 3), each jaw member including a planar sealing surface (5 & 7). The jaw members are assembled with the first and second jaw members in a required orientation such that the planar sealing surface (5) of the first jaw member (2) is at a predetermined orientation with respect to the sealing surface (7) of the second jaw member (3). The first and second jaw members are held in the required orientation, and pivot holes (11 & 12) are formed in the first and second jaw members while they are held in the required orientation. When a pivot pin is inserted through the pivot holes in the first and second jaw members, the first and second jaw members are assembled into a pair of jaws.

Claims

1. A method of manufacturing a pair of jaws for an electrosurgical instrument, comprising the steps of: manufacturing first and second jaw members, each jaw member including a planar sealing surface, assembling the first and second jaw members in a required orientation such that the planar sealing surface of the first jaw member is at a predetermined orientation with respect to the sealing surface of the second jaw member, holding the first and second jaw members in the required orientation, forming a pivot hole in the first and second jaw members while they are held in the required orientation, and inserting a pivot pin through the pivot hole in the first and second jaw members to assemble the first and second jaw members into a pair of jaws.

2. A method according to claim 1, wherein the required orientation is such that the planar sealing surface of the first jaw member is parallel to the planar sealing surface of the second jaw member.

3. A method according to claim 1, wherein the pivot hole is formed in the first and second jaw members in a single operation.

4. A method according to claim 1, wherein the step of forming the pivot hole comprises drilling through the first and second jaw members with a drill bit.

5. A method according to claim 1, including the initial steps of forming an initial hole in the first and second jaw members before the assembly step, and filling the holes with a softer material before assembling the first and second jaw members.

6. A method according to claim 5, wherein the step of forming the pivot hole in the first and second jaw members while they are held in the required orientation comprises forming the hole through the softer material.

7. A method according to claim 6, wherein the diameter of the pivot hole is less than the diameter of the initial hole in each of the first and second jaw members.

8. A method according to claim 5, wherein the softer material is a polymeric material.

9. A method of manufacturing a pair of jaws for an electrosurgical instrument, comprising the steps of: manufacturing first and second jaw members, each jaw member including a planar sealing surface, and an initial pivot hole, filling the initial pivot hole in each of the first and second jaw members with a softer material, assembling the first and second jaw members in a required orientation such that the planar sealing surface of the first jaw member is at a predetermined orientation with respect to the sealing surface of the second jaw member, holding the first and second jaw members in the required orientation, forming a final pivot hole in the softer material while the first and second jaw members are held in the required orientation, and inserting a pivot pin through the final pivot hole in the first and second jaw members to assemble the first and second jaw members into a pair of jaws.

10. A method according to claim 9, wherein the diameter of the final pivot hole is less than the diameter of the initial pivot hole in each of the first and second jaw members.

11. A method according to claim 9, wherein the softer material is a polymeric material.

Description

DESCRIPTION OF THE DRAWINGS

[0022] Embodiments of the invention will now be further described, by way of example only, with reference to the accompanying drawings, in which:

[0023] FIG. 1 is a schematic side view of a pair of jaws as part of a manufacturing method according to an embodiment of the present invention,

[0024] FIG. 2 is a side view of the jaws of FIG. 1 shown in a subsequent manufacturing step,

[0025] FIG. 3 is a side view of the jaws of FIGS. 1 & 2 shown in a further manufacturing step,

[0026] FIG. 4 is a side view of a pair of jaws as part of an alternative embodiment of manufacturing method according to the present invention,

[0027] FIG. 5 is a side view of the jaws of FIG. 4 shown in a subsequent manufacturing step,

[0028] FIG. 6 is a side view of the jaws of FIGS. 4 & 5 shown in a further manufacturing step, and

[0029] FIG. 7 is a side view of the jaws of FIGS. 4 to 6 shown in a subsequent manufacturing step.

DESCRIPTION OF THE EMBODIMENTS

[0030] Referring to FIG. 1, an end effector shown generally at 1 comprises an upper jaw 2 and a lower jaw 3. Upper jaw 2 has a jaw body 4 and a substantially planar tissue sealing surface 5, while lower jaw 3 has a jaw body 6 and a corresponding planar tissue sealing surface 7. The sealing surfaces 5 & 7 are substantially parallel one to the other, and are separated by a plurality of stop members 8 located on one or both of the jaws.

[0031] Lower jaw body 6 is provided with an angled cam slot 9, while upper jaw body 6 has a corresponding oppositely angled cam slot 10, shown in dotted line detail. The jaws 2 & 3 are shown in FIG. 1 located together in a desired orientation with the sealing surfaces 5 & 7 parallel to one another, but the jaws are not at this stage connected to each other.

[0032] The jaws 2 & 3 are shown in FIG. 2 clamped in position, with clamps (not shown) engaging the jaw bodies 4 & 6 to hold them in the desired position. While clamped in position, a drill bit (not shown) drills a pivot hole 11 in jaw body 6, as shown in FIG. 3. The drill bit continues through jaw body 6 to drill a corresponding pivot hole 12 (though not directly visible in FIG. 3 as behind hole 11) in the jaw body 4. Pivot holes 11 & 12 are aligned such that when a pivot pin (not shown) is inserted through holes 11 & 12 the jaws 2 & 3 are assembled in their desired orientation with the sealing surfaces 5 & 7 parallel to one another.

[0033] FIG. 4 shows an alternative arrangement in which the jaws 2 & 3 are shown as before, with sealing surfaces 5 & 7 shown parallel one to another. The jaws of FIG. 4 are different from those of FIG. 1 in that they have been pre-drilled with initial large diameter holes 13 & 14. The jaws 2 & 3 are then placed into moulds and injection moulded such that the holes 13 & 14 are filled with a polymeric material to form polypropylene inserts 15, as shown in FIG. 5. Once the polypropylene material of the inserts 15 has hardened, the jaws are clamped in position as before, as shown in FIG. 6. While clamped in position, a drill bit (not shown) drills a pivot hole 16 through the polypropylene insert 15 in the lower jaw body 6, as shown in FIG. 7. The drill bit then continues through jaw body 6 to drill a corresponding pivot hole 17 (again not directly visible in FIG. 7 as behind hole 16) through the insert 15 in the jaw body 4. As the drill bit is drilling through polymeric material rather than through the metallic jaw bodies, the process is easier and with less vibration. Once again, pivot holes 16 & 17 are aligned such that when a pivot pin (not shown) is inserted through holes 16 & 17 the jaws 2 & 3 are assembled in their desired orientation with the sealing surfaces 5 & 7 parallel to one another.

[0034] Those skilled in the art will appreciate that modifications to the above can be made without departing from the scope of the present invention, and that alternative configurations of components can be employed. For example, although the desired orientation of the sealing surfaces 5 & 7 in the illustrated embodiments is with the sealing surfaces parallel to one another, this may not necessarily be the case. There may be circumstances where a desired orientation is with the sealing surfaces not parallel, but with the jaws 2 & 3 either “toed-in” (such that the distance between the sealing surfaces is greater towards the rear of the jaws as compared with the front), or “toed-out” (such that the distance between the sealing surfaces is greater towards the front of the jaws as compared with the rear). The key element is the formation of the pivot holes with the jaws already in their desired orientation, as opposed to pre-forming the pivot holes and then assembling the jaws.