Method and force-limiting handle mechanism for a surgical instrument

• US 20080083813A1
• Filed: 10/05/2006
• Published: 04/10/2008
• Est. Priority Date: 10/05/2006
• Status: Active Grant

• Current Assignee: Covidien LP (Medtronic Plc)
• Original Assignee: Covidien LP (Medtronic Plc)
• Inventors: Desantis, Robert J., Scirica, Paul A., Zemlok, Michael
• Granted Patent: US 8,708,210 B2
• Time in Patent Office: Days
• US Class Current: 227/181.1
• 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 17/10 for applying or removing wound clamps, e.g. containing only one clamp or staple A61B17/076 takes precedence; containing multiple wound clamps A61B17/068; Wound clamp magazines containers, packaging elements or packages specially adapted for particular articles or with special means for dispensing contents B65D83/00, B65D85/00
• CPC Class Codes: A61B 17/2909 Handles
• CPC Class Codes: A61B 2017/2912 transmission of forces to actuating rod or piston
• CPC Class Codes: A61B 2017/292 connection of actuating rod to handle, e.g. ball end in recess
• CPC Class Codes: A61B 2017/2923 Toothed members, e.g. rack and pinion
• CPC Class Codes: A61B 2017/2925 Pistol grips
• CPC Class Codes: A61B 90/03 Automatic limiting or abutting means, e.g. for safety
• CPC Class Codes: Y10T 74/20612 Hand

Abstract

A safety handle assembly for use with a surgical instrument having an operative distal end portion is disclosed. The handle assembly includes a handle housing and a drive element movably mounted within the handle housing and connected to an associated operative distal end portion. A drive assembly is positioned within the handle housing and is engageable with the drive element to move the drive element within the handle housing. An actuator is movably mounted on the handle housing and an adjustable force-limiting mechanism is interposed between the drive assembly and the actuator. A force-limiting mechanism releasably connects the actuator to the drive assembly. The force-limiting mechanism is adjustable to preset the force at which the actuator separates or breaks away from the drive assembly.

Claims

1. A handle assembly for use with a surgical instrument having an operative distal end portion comprising:

a handle housing;

a drive element movably mounted within the handle housing and connected to an operative distal end portion;

a drive assembly positioned within the handle housing and engageable with the drive element to move the drive element within the handle housing;

an actuator movably mounted on the handle housing; and

a force-limiting mechanism interposed between the drive assembly and the actuator, the force-limiting mechanism releasably connecting the actuator to the drive assembly.

2. The handle assembly as recited in claim 1, wherein the force-limiting mechanism includes a connecting rod, a first end of the connecting rod is attached to the drive assembly and a second end of the connecting rod is mounted within the actuator.

3. The handle assembly as recited in claim 2, wherein the force-limiting mechanism includes a spring positioned within the actuator and adjacent the second end of the connecting rod.

4. The handle assembly as recited in claim 3, wherein the force-limiting mechanism includes an adjustment screw positioned within the actuator and engageable with the spring to vary the force within the spring.

5. The handle assembly as recited in claim 2, wherein the connecting rod has a protrusion and the drive assembly includes a cut out portion, the protrusion being releasably engageable within the cut out portion.

6. The handle assembly as recited in claim 5, wherein the drive assembly includes an upper carrier and a lower carrier, the upper carrier being connected to a first end of the connecting rod.

7. The handle assembly as recited in claim 6, wherein the cut out portion of the drive assembly is included in the lower carrier for releasable engagement with the protrusions on the connecting rod.

8. The handle assembly as recited in claim 7, wherein the connecting rod has a ramp for supporting a portion of the lower carrier when the drive assembly is disconnected from the connecting rod.

9. The handle assembly as recited in claim 8, wherein the lower carrier is rotatably mounted on the handle housing and defines a first axis with a pivot point on the upper carrier.

10. The handle assembly as recited in claim 9, wherein the connecting rod defines a second axis with a connection point on the upper carrier.

11. The handle assembly as recited in claim 10, wherein the first and second axes are substantially parallel when the protrusions are engaged with the cut outs.

12. The handle assembly as recited in claim 10, wherein the first and second axes are substantially nonparallel when the protrusions are not engaged with the cut outs.

13. The handle assembly as reciting claim 12, wherein the lower carrier has at least one flexible arm containing the cut out.

14. The handle assembly as recited in claim 13, wherein the at least one flexible arm is flexible outwardly relative to the lower carrier when the protrusion is disconnected from the cut out.

15. The handle assembly as recited in claim 14, wherein the connecting rod includes a ramp and the at least one flexible arm rests upon the ramp when the protrusion on the connecting rod is disengaged from the cut out on the at least one flexible arm.

16. A handle assembly for use with a surgical instrument having an operative distal end portion comprising:

a handle housing;

a rack movably mounted within the handle housing and connected to an operative distal end portion;

a drive assembly positioned within the handle housing, the drive assembly including a pawl engageable with the rack;

a trigger pivotally mounted on the handle housing; and

an adjustable force-limiting mechanism releasably attached to a portion of the drive assembly and mounted for movement within the trigger, the adjustable force-limiting mechanism releasably connecting the trigger to the drive assembly.

17. The handle assembly as recited in claim 16, wherein the adjustable force-limiting mechanism includes a connecting rod having a first end connected to a portion of the drive assembly and a second end movably mounted within the trigger.

18. The handle assembly as recited in claim 17, wherein the adjustable force-limiting mechanism includes a spring mounted within the trigger such that a first end of the spring is engageable with the second end of the connecting rod.

19. The handle assembly as recited in claim 18, wherein the adjustable force-limiting mechanism includes an adjustment screw mounted within the trigger such that rotation of the adjustment screw alters the pressure within the spring.

20. The handle assembly as recited in claim 19, wherein the adjustable force-limiting mechanism includes a bushing mounted within the trigger, the bushing being positioned between the spring and the adjustment screw.

21. A handle assembly for use with a surgical instrument having an operative distal end portion comprising:

a handle housing;

a drive element movably mounted within the handle housing and connected to an operative distal end portion for performing surgery;

an actuator movably mounted on the handle housing; and

a force-limiting mechanism disposed between the drive element and the actuator, the force-limiting mechanism having a breakaway force;

the force-limiting mechanism being attached to the actuator so that the force-limiting mechanism moves with the actuator when the force applied to the actuator is less than the breakaway force and so that the force-limiting mechanism pivots with respect to the actuator when the force applied to the actuator meets the breakaway force, the force-limiting mechanism applying a drive force to the drive element when the force applied to the actuator is less than the breakaway force.

22. The handle assembly as recited in claim 21, wherein the force-limiting mechanism includes a lower carrier.

23. The handle assembly as recited in claim 22, wherein the force-limiting mechanism includes a connecting rod connected to the actuator and releasably connected to the lower carrier.

24. The handle assembly as recited in claim 23, wherein the connecting rod is slidably disposed in the actuator and a spring is positioned between the actuator and the connecting rod.

25. The handle assembly as recited in claim 24, wherein the lower carrier is pivotably connected to the actuator.

26. The handle assembly as recited in claim 25, wherein the lower carrier is pivotably connected to an upper carrier, the upper carrier being pivotably connected to the connecting rod.

27. The handle assembly as recited in claim 22, wherein the drive element comprises a rack having at least one tooth and further comprising a pawl pivotably connected to the force-limiting mechanism for engagement with the rack.

28. The handle assembly as recited in claim 21, wherein the force-limiting mechanism includes a carriage in mechanical cooperation with the actuator.

29. The handle assembly as recited in claim 28, further comprising a pawl pivotably connected to the carriage.

30. The handle assembly as recited in claim 29, wherein the force-limiting mechanism includes a plunger slidably connected to the actuator.

31. The handle assembly as recited in claim 30, wherein the plunger is slidably disposed at least partially within the actuator.

32. The handle assembly as recited in claim 31, wherein at least one spring is disposed between the plunger and the actuator.

33. The handle assembly as recited in claim 30, wherein the carriage includes an angled surface for engaging at least a portion of the plunger.

34. The handle assembly as recited in claim 33, wherein the plunger includes an angled face for engaging the angled surface, the angled surface and angled face being arranged so that the carriage is able to depress the plunger.

35. The handle assembly as recited in claim 34, wherein the plunger is biased toward the carriage with a predetermined amount of force.

36. A method of controlling the maximum amount of force applied to an end effector by a handle assembly comprising:

providing a handle assembly having a handle housing, a rack movably mounted within the handle housing, a drive assembly mounted within the handle housing and engageable with the rack, a trigger pivotally mounted within the handle housing and a clutch mechanism interposed between the drive assembly and the trigger such that the clutch mechanism releasably connects the trigger to the drive assembly;

urging at least a portion of the clutch mechanism into engagement with the drive assembly by a predetermined force; and

releasing the clutch mechanism from the drive assembly in response to a predetermined amount of force applied to the rack.

37. The method as recited in claim 36, wherein the step of urging at least a portion of the clutch mechanism includes urging a spring biased plunger associated with the clutch mechanism into engagement with the drive assembly.