# US 2014/0150600 A1 · Method and force-limiting handle mechanism for a surgical instrument > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0150600 A1 - Document ID: US20140150600A1 - Status: Published application - Kind: A1 - Application number: 14/173,220 - Filed: 2014-02-05 - Published: 2014-06-05 - Earliest claimed: 2006-10-05 - Assignees: Covidien LP - Applicants: Covidien LP - Inventors: Michael Zemlok; Paul A. Scirica; Robert J. DeSantis - Web page: https://patentgrep.com/patent/US20140150600A1 ## CPC - A61B 17/2909: {Handles} - A61B 17/068: Surgical staplers {, e.g. containing multiple staples or clamps}({staplers containing only one staple A61B17/10; magazines or containers for staples A61B17/105;} for performing anastomosis A61B17/115; {staplers in general B25C5/00}) - 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 - A61B 90/03: {Automatic limiting or abutting means, e.g. for safety} - A61B 2017/2912: {transmission of forces to actuating rod or piston} - A61B 2017/292: {connection of actuating rod to handle, e.g. ball end in recess} - A61B 2017/2923: {Toothed members, e.g. rack and pinion} - A61B 2017/2925: {Pistol grips} - Y10T 74/20612: Hand - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## 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 ### Claim 1 (canceled) ### Claim 2 A handle assembly for use with a surgical instrument having an operative distal end portion comprising: a drive assembly; a trigger disposed in mechanical cooperation with the drive assembly; and an adjustable force-limiting mechanism releasably connecting the trigger to the drive assembly, the adjustable force-limiting mechanism including a connecting rod, a first portion of the connecting rod being connected to a portion of the drive assembly, a second portion of the connecting rod being movably mounted within the trigger. ### Claim 3 (depends on 2) The handle assembly as recited in claim 2, 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. ### Claim 4 (depends on 3) The handle assembly as recited in claim 3, wherein the adjustable force-limiting mechanism includes an adjustment screw mounted within the trigger such that rotation of the adjustment screw alters pressure within the spring. ### Claim 5 A handle assembly for use with a surgical instrument having am 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. ### Claim 6 (depends on 5) The handle assembly as recited in claim 5, wherein the force-limiting mechanism includes a lower carrier. ### Claim 7 (depends on 6) The handle assembly as recited in claim 6, wherein the force-limiting mechanism includes a connecting rod connected to the actuator and releasably connected to the lower carrier. ### Claim 8 (depends on 7) The handle assembly as recited in claim 7, wherein the connecting rod is slidably disposed in the actuator and a spring is positioned between the actuator and the connecting rod. ### Claim 9 (depends on 8) The handle assembly as recited in claim 8, wherein the lower carrier is pivotably connected to the actuator. ### Claim 10 (depends on 9) The handle assembly as recited in claim 9, wherein the lower carrier is pivotably connected to an upper carrier, the upper carrier being pivotably connected to the connecting rod. ### Claim 11 (depends on 6) The handle assembly as recited in claim 6, 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. ### Claim 12 (depends on 5) The handle assembly as recited in claim 5, wherein the force-limiting mechanism includes a carriage in mechanical cooperating with the actuator. ### Claim 13 (depends on 12) The handle assembly as recited in claim 12, further comprising a pawl pivotably connected to the carriage. ### Claim 14 (depends on 13) The handle assembly as recited in claim 13, wherein the force-limiting mechanism includes a plunger slidably connected to the actuator. ### Claim 15 (depends on 14) The handle assembly as recited in claim 14, wherein the plunger is slidably disposed at least partially within the actuator. ### Claim 16 (depends on 15) The handle assembly as recited in claim 15, wherein at least one spring is disposed between the plunger and the actuator. ### Claim 17 (depends on 14) The handle assembly as recited in claim 14, wherein the carriage includes an angled surface for engaging at least a portion of the plunger. ### Claim 18 (depends on 17) The handle assembly as recited in claim 17, 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. ### Claim 19 (depends on 18) The handle assembly as recited in claim 18, wherein the plunger is biased toward the carriage with a predetermined amount of force. ### Claim 20 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, wherein a portion of the clutch mechanism is pivotably attached to the drive assembly about a pivot, wherein a portion of the clutch mechanism is movably mounted within the trigger, and wherein the pivot is stationary with respect to the handle housing; 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. ### Claim 21 (depends on 20) The method as recited in claim 20, 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.