Circular Stapler With Controlled Tissue Compression

• US 20120273545A1
• Filed: 04/29/2011
• Published: 11/01/2012
• Est. Priority Date: 04/29/2011
• Status: Active Grant

• Current Assignee: Covidien LP (Medtronic Plc)
• Original Assignee: Covidien LP (Medtronic Plc)
• Inventors: Mozdzierz, Patrick
• Granted Patent: US 8,490,850 B2
• Time in Patent Office: Days
• US Class Current: 227/175.1
• CPC Class Codes: A61B 17/068 Surgical staplers , e.g. containing multiple staples or clampsstaplers containing only one staple A61B17/10; magazines or containers for staples A61B17/105; for performing anastomosis A61B17/115; staplers in general B25C5/00
• CPC Class Codes: A61B 17/07207 the staples being applied sequentially
• CPC Class Codes: A61B 17/115 Staplers for performing anastomosis in a single operation
• CPC Class Codes: A61B 17/1155 Circular staplers comprising a plurality of staples
• CPC Class Codes: A61B 2017/00022 Sensing or detecting at the treatment site
• CPC Class Codes: A61B 2017/07214 Stapler heads
• CPC Class Codes: A61B 2017/07242 achieving different staple heights during the same shot, e.g. using an anvil anvil having different heights or staples of different sizes
• CPC Class Codes: A61B 2017/07257 characterised by its anvil
• CPC Class Codes: A61B 2090/031 torque limiting

Abstract

There are provided torque limiting mechanisms for use in tissue clamping surgical instruments. The torque limiting mechanisms generally include a driven member, engageable with an approximating mechanism of the surgical instruments, and having a driven surface and a driving member having a driving surface engageable with the driven surface of the driven member. The driving member is rotatable relative to the driven member such that the driving surface of the driving member slips relative to or dissengages from the driven surface of the driven member at a predetermined engagement pressure.

Claims

1. A torque limiting mechanism for use in a surgical instrument that compresses tissue comprising:

a driven member engageable with an approximating mechanism of a surgical instrument, the driven member having a driven surface; and

a driving member having a driving surface engageable with the driven surface of the driven member and connected to the clamping actuator of the instrument, wherein the driving surface of the driving member slips relative to the driven surface of the driven member at a predetermined engagement pressure; and

a torque control having a member that adjusts the pressure applied by the driving member to the driven member.

2. The torque limiting mechanism as recited in claim 1, wherein driving member is rotatable relative to the driven member.

3. The torque limiting mechanism as recited in claim 2, wherein the driving surface frictionally engages the driven surface.

4. The torque limiting mechanism as recited in claim 2, wherein the driving surface and the driven surface have interengaging structure.

5. The torque limiting mechanism as recited in claim 4, wherein the driving surface and the driven surface have interengaging teeth.

6. The torque limiting mechanism as recited in claim 4, wherein the interengaging structure is a detent mechanism.

7. The torque limiting mechanism as recited in claim 6, further comprising at least one movable connector between the driving surface and the driven surface.

8. The torque limiting mechanism as recited in claim 6, wherein at least one of the driving surface and driven surface includes cups and the other of the driving surface and driven surface supports balls removably engageable with the cups.

9. The torque limiting mechanism as recited in claim 2, further comprising a spring engageable with the driving member, wherein the driving member is spring biased into engagement with the driven member.

10. The torque limiting mechanism as recited in claim 9, wherein the member of the torque control engages with the biasing spring.

11. The torque limiting mechanism as recited in claim 10, wherein the torque control includes a hook engageable with the biasing spring and a slide member.

12. A surgical instrument comprising:

a body portion;

a first clamping member mounted on the body portion and a second clamping member movable relative to the first clamping member;

an approximating mechanism for moving the second clamping member relative to the first clamping member, the approximating mechanism including a longitudinally movable drive screw having a helical groove formed therein and a rotatable sleeve mounted about the drive screw, the rotatable sleeve including a drive pin extending into the helical groove such that rotation of the rotatable sleeve longitudinally translates the drive screw within the body portion;

a torque limiting mechanism engageable with the rotatable sleeve, wherein at least a portion of the torque limiting mechanism slips relative to the rotatable sleeve at a predetermined engagement pressure.

13. The surgical instrument as recited in claim 12, wherein the torque limiting mechanism includes a driven surface affixed to the rotatable sleeve and a driving surface engageable with the driven surface.

14. The surgical instrument as recited in claim 13, wherein the driving surface frictionally engages the driven surface.

15. The surgical instrument as recited in claim 13, wherein the driving surface and the driven surface have interengaging structure.

16. The surgical instrument as recited in claim 15, wherein the driving surface and the driven surface have interengaging teeth.

17. The surgical instrument as recited in claim 15, wherein the interengaging structure is a detent mechanism.

18. The surgical instrument as recited in claim 17, wherein at least one of the driving surface and driven surface includes cups and the other of the driving surface and driven surface supports balls removably engageable with the cups.

19. The surgical instrument as recited in claim 12, further comprising a spring engageable with the driving member, wherein the driving member is spring biased into engagement with the driven member.

20. A method of preventing over compression of tissue between first and second clamping members of a surgical instrument comprising:

providing a surgical instrument including a body portion;

a first clamping member mounted on the body portion and a second clamping member movable relative to the first clamping member;

an approximating mechanism for moving the second clamping member relative to the first clamping member, the approximating mechanism including a longitudinally movable drive screw having a helical groove formed therein and a rotatable sleeve mounted about the drive screw, the rotatable sleeve including a drive pin extending into the helical groove such that rotation of the rotatable sleeve longitudinally translates the drive screw within the body portion and an approximation knob engageable with the rotatable sleeve;

a torque limiting mechanism engageable with the rotatable sleeve;

rotating the approximation knob to rotate rotatable sleeve such that at least a portion of the torque limiting mechanism slips relative to the rotatable sleeve at a predetermined engagement pressure.