GB2566915A

GB2566915A - Jaw member

Info

Publication number: GB2566915A
Application number: GB1701781.5A
Authority: GB
Inventors: Atwell Tony
Original assignee: Gyrus Medical Ltd
Current assignee: Gyrus Medical Ltd
Priority date: 2017-02-03
Filing date: 2017-02-03
Publication date: 2019-04-03
Anticipated expiration: 2037-02-03
Also published as: GB201701781D0; GB2566915B

Abstract

A jaw member 2 for a surgical instrument comprises a jaw housing 5 and a jaw body 6. The jaw body 6 includes a planar tissue sealing surface 10. The jaw housing 5 includes a first steadily curved surface 11 extending longitudinally of the jaw member 2. The jaw body 6 includes a complementary second curved surface 12 matching the first curved surface 11. The jaw body 6 is located on the jaw housing 5 such that it is translatable longitudinally with respect to the jaw housing 5, with the second curved surface 12 sliding over the first curved surface 11 to adjust the angle of the sealing surface 10. With the sealing surface 10 disposed at a desired angle, the jaw body 6 is secured to the jaw housing 5 by a locking means. Preferably a first one of either the jaw housing 5 or the jaw body 6 includes a longitudinal slot, and the other one of either the jaw housing 6 or the jaw body 6 includes a longitudinal rail adapted to be received in the slot. The locking means may be an adhesive. Also an end effector for a surgical instrument including a jaw member 2.

Description

JAW MEMBER

This invention relates to a jaw member for a surgical instrument, and to a method for assembling such a jaw member. Jaw members such as these are commonly used for the treatment of tissue in surgical intervention, most commonly in “keyhole” or minimally invasive surgery, but also in “open” surgery.

It is known to provide an electro surgical instrument in which jaw members grasp tissue for the purpose of sealing the tissue, and it has been found that this is achieved most effectively when the surfaces grasping the tissue are parallel one to the other. However, this is not always easy to achieve, especially where the jaw members are very small, as is often the case for laparoscopic or endoscopic instruments. The present invention attempts to provide a jaw member where the angle of the sealing surface is able to be easily adjusted during assembly.

Accordingly, a jaw member for a surgical instrument is provided, the jaw member comprising a jaw housing and a jaw body, the jaw body including a planar sealing surface adapted to contact tissue coming into contact with the jaw member, the jaw housing including a first steadily curved surface extending longitudinally of the jaw member, the jaw body including a complementary second curved surface matching the first curved surface of the jaw housing, the jaw body being located on the jaw housing such that it is translatable longitudinally with respect to the jaw housing with the second curved surface of the jaw body sliding over the first curved surface of the jaw housing to adjust the angle of the planar sealing surface, and locking means for securing the jaw body with respect to the jaw housing when the planar sealing surface is disposed at the desired angle.

By providing complementary curved surfaces on the jaw housing and the jaw body, the angle of the planar sealing surface may be easily adjusted, merely by sliding the jaw body longitudinally with respect to the jaw housing. Conceivably, by bringing a pair of jaw members together during assembly such that the sealing surface on each jaw member contacts its opposite number, one or both jaw bodies will self-adjust by virtue of the contact between the sealing surfaces to bring the sealing surfaces into parallel registration.

Conveniently, the first curved surface is substantially concave and the second curved surface is substantially convex. Alternatively, the first curved surface is substantially convex and the second curved surface is substantially concave. Whichever arrangement is employed, the curved surface converts a longitudinal movement of the jaw body into a change in angle of the sealing surface, such that a desired alignment of the respective sealing surfaces can be easily accomplished.

Typically, a first one of either the jaw housing or the jaw body includes a longitudinal slot, and the other one of either the jaw housing or the jaw body includes a longitudinal rail adapted to be received in the slot. In this way, the jaw body can be longitudinally translated with respect to the jaw housing, while being retained in the slot. The longitudinal rail is preferably provided with a complex cross-section, such that it is retained in the slot while still able to move longitudinally with respect thereto. By “complex”, it is meant that the cross-section of the slot is more than just a U-shaped slot, such that the rail is keyed to remain within the slot, yet still able to move longitudinally with respect thereto. Conveniently, the rail is provided with a generally T-shaped crosssection. Typically, the slot has an upper section with a first width, and a lower section with a second width, the second width being greater than the first width, such that the Tshaped rail can be accommodated within the slot.

According to a convenient arrangement, the jaw housing is provided with the rail, and the jaw body is provided with the slot. Alternatively, the slot may be provided in the jaw housing, and the rail provided on the jaw body. Whichever arrangement is employed, the jaw body is longitudinally movable with respect to the jaw housing, at least until the locking means is applied. Typically, the locking means is an adhesive, applied once the jaw body on each jaw member is in a satisfactory position such that its sealing surface is parallel with that of the opposing jaw member.

The invention further resides in an end effector for a surgical instrument including one or both jaw members as previously described. Typically, at least one of the jaw members is movable relative to the other between a first open position in which the jaw members are disposed in a spaced relation relative to one another, and a second closed position in which the jaw members cooperate to grasp tissue therebetween.

The invention also resides in a method of assembling an end effector for a surgical instrument comprising the steps of

a) providing a pair of jaw members, each of the jaw members including a substantially planar sealing surface adapted to contact tissue grasped between the jaw members, at least one of the jaw members comprising a jaw housing and a jaw body, the jaw body including the planar sealing surface, the jaw housing including a first steadily curved surface extending longitudinally of the jaw member, the jaw body including a complementary second curved surface matching the first curved surface of the jaw housing,

b) longitudinally translating at least one of the jaw bodies with respect to its associated jaw housing such that the second curved surface of the jaw body slides over the first curved surface of the jaw housing to adjust the angle of the planar sealing surface until the sealing surfaces of the first and second jaw members are in a desired orientation with respect to one another, and

c) locking the jaw body with respect to the jaw housing such that the sealing surfaces of the first and second jaw members remain in the desired orientation with respect to one another.

Preferably, the desired orientation is with the sealing surfaces parallel to one another. The step of longitudinally translating at least one of the jaw bodies with respect to its associated jaw housing can either be carried out manually, or alternatively by bringing the jaw members together such that the sealing surfaces of each of the jaw members contact one another. If the sealing surfaces are non-parallel, the sealing surfaces will come into contact with each other at one end before they do so at the other end. Continued closing of the jaw members will move one or both of the jaw bodies with respect to their associated jaw housings until the sealing surfaces become parallel. Once this happens (and provided the sealing surfaces are acceptably aligned with regard to the overall longitudinal axis of the jaw members), the jaw bodies can be locked in position, typically by the application of an adhesive.

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

Figure 1 is a schematic perspective view of a jaw member in accordance with the present invention,

Figure 2 is a schematic side view of the jaw member of Figure 1,

Figure 3 is a schematic side view of the jaw member of Figure 1 shown in an initial stage of assembly,

Figure 4 is a schematic side view of the jaw member of Figure 1 shown in a final stage of assembly,

Figure 5 is a perspective view, shown partly in cross-section, of the jaw member of Figure 1, and

Figure 6 is an exploded perspective view of an alternative embodiment of jaw member in accordance with the present invention.

Referring to Figures 1 to 4, an end effector for an electrosurgical forceps instrument is shown generally at 1, and comprises a first jaw member 2 pivotably connected to a second jaw member 3 by means of a pivot 4. Jaw member 2 comprises a jaw housing 5 and a jaw body 6, the jaw body including a planar sealing surface 7. Similarly, jaw member 3 comprises a jaw housing 8 and a jaw body 9, the jaw body including a planar sealing surface 10. Sealing surfaces 7 & 10 are complementary such that when the jaw members 2 & 3 are moved to their closed position, the sealing surfaces 7 & 10 cooperate to grasp tissue (not shown) therebetween.

Jaw housing 5 is provided with a concave lower surface 11, and jaw body 6 has a convex upper surface 12, the concave and convex surfaces mating one with the other. Similarly, jaw housing 8 is provided with a concave upper surface 13, and jaw body 9 has a convex lower surface 14, the concave and convex surfaces mating with each other in similar fashion.

As shown in Figure 5, jaw housings 5 & 8 are provided with T-shaped rails 15 & 16, received in complementary slots 17 & 18 in the jaw bodies 6 & 9. In this way, jaw bodies 6 & 9 are able to move back and forth longitudinally with respect to jaw housings 5 & 8, sliding along the rails 15 & 16. As the jaw bodies 6 & 9 slide with respect to the jaw housings 5 & 8, the concave and convex surfaces ensure that any longitudinal movement of the jaw bodies 6 & 9 also produces a change in the angle of the sealing surfaces 7 & 10.

Figure 2 shows a first stage in the assembly of the end effector 1, where the jaw bodies 6 & 9 are located on the rails 15 & 16 such that they are retained on the jaw housings 5 & 8 yet are free to slide longitudinally. Figure 3 shows the next step, in which the jaw members are brought closer together. However, due to the non-alignment of the sealing surfaces 7 & 10, one end of the jaw body 6 (in this case the proximal end of the jaw body) comes into contact with the respective end of the jaw body 9 before the opposite end of the jaw body does. Figure 3 shows the proximal end of the jaw bodies approaching one another at 19, while the distal end is further apart at 20.

This situation can be corrected by an assembly operative easily and quickly, simply by moving the jaw bodies 6 & 9 along the rails 15 & 16 a small distance in a distal direction to the position shown in Figure 4. After the jaw bodies 6 & 9 have been moved in this way, the sealing surface 7 on jaw body 6 is now parallel with the sealing surface 10 on jaw body 9. The distance between the jaw bodies at their distal and proximal ends is now substantially equal, as is the distance between them at all points in between.

Once in the required position as shown in Figure 4, the jaw bodies 6 & 9 can be secured in position on their respecting jaw housings 5 & 8 by the application of a fast setting penetrative adhesive (not shown). This fixes the jaw members with the sealing surfaces 7 & 10 parallel to one another, the preferred arrangement for the effective sealing of tissue.

Figure 6 shows that the slots 17 & 18 do not need to extend continuously along the jaw bodies, nor do the rails 15 & 16 along the jaw housings. As the longitudinal movement of the jaw bodies only needs to be relatively small, the slots and rail can be constituted by complementary tabs 21 & 22, the tabs 21 being located on the jaw housings and the tabs 22 on the jaw bodies. The tabs serve the same purpose retaining the jaw bodies within the jaw housings, while allowing longitudinal movement therebetween.

It will be appreciated by those skilled in the art that various changes can be made without departing from the scope of the present invention. For example, various mechanical locking arrangements can be employed instead of adhesive, and various other curved shapes can be employed for the complementary surfaces 11, 12, 13 & 14. Similarly, other arrangements to the slots and rails can be employed as long as they allow for longitudinal translation between the jaw bodies and the jaw housings. The relative orientation between the sealing surfaces is not necessarily with them parallel to one another, and there may be circumstances where it is desired to provide sealing surfaces with a preset angle therebetween. Whatever the desired orientation, the present invention allows the angle of the sealing surfaces to be adjusted during assembly, as required.

Claims

1. A jaw member for a surgical instrument, the jaw member comprising a jaw housing and a jaw body, the jaw body including a planar sealing surface adapted to contact tissue coming into contact with the jaw member, the jaw housing including afirst steadily curved surface extending longitudinally of the jaw member, the jaw body including a complementary second curved surface matching the first curved surface of the jaw housing, the jaw body being located on the jaw housing such that it is translatable longitudinally with respect to the jaw housing with the second curved surface of the jaw body sliding over the first curved surface of the jaw housing to adjust the angle of the planar sealing surface, and locking means for securing the jaw body with respect to the jaw housing when the planar sealing surface is disposed at the desired angle.

2. A jaw member according to claim 1, wherein the first curved surface is substantially concave and the second curved surface is substantially convex.

3. A jaw member according to claim 1, wherein the first curved surface is substantially convex and the second curved surface is substantially concave.

4. A jaw member according to any of claims 1 to 3, wherein a first one of either the jaw housing or the jaw body includes a longitudinal slot, and the other one of either the jaw housing or the jaw body includes a longitudinal rail adapted to be received in the slot.

5. A jaw member according to claim 4, wherein the longitudinal rail is provided with a complex cross-section, such that it is retained in the slot while still able to move longitudinally with respect thereto.

6. A jaw member according to claim 5, wherein the rail is provided with a generally T-shaped cross-section.

7. A jaw member according to claim 6, wherein the slot has an upper section with a first width, and a lower section with a second width, the second width being greater than the first width, such that the T-shaped rail can be accommodated within the slot.

8. A jaw member according to any of claims 4 to 7, wherein the jaw housing is provided with the rail, and the jaw body is provided with the slot.

9. A jaw member according to any preceding claim, wherein the locking means is an adhesive.

10. An end effector for a surgical instrument including a jaw member according to any of claims 1 to 9.

11. An end effector according to claim 10, including two jaw members, both of which are according to any of claims 1 to 9.

12. An end effector according to claim 10 or claim 11, wherein at least one of the jaw members is movable relative to the other between a first open position in which the jaw members are disposed in a spaced relation relative to one another, and a second closed position in which the jaw members cooperate to grasp tissue therebetween.

13. A method of assembling an end effector for a surgical instrument comprising the steps of

14. A method according to claim 13, wherein the step of longitudinally translating at least one of the jaw bodies with respect to its associated jaw housing is carried out manually.

15. A method according to claim 13, wherein the step of longitudinally translating at least one of the jaw bodies with respect to its associated jaw housing is carried out by bringing the jaw members together such that the sealing surfaces of each of the jaw members contact one another.

16. A method according to any of claims 13 to 15, wherein the desired orientation is with the sealing surfaces of the first and second jaw members parallel to one another.