Dual stage energy activation for electrosurgical shears

A surgical instrument comprising:

• (a) an end effector, wherein the end effector comprises:
• (i) a first jaw,
• (ii) a second jaw coupled with the first jaw, wherein the second jaw is operable to move between an open position and a closed position, and
• (iii) an electrode assembly;
• (b) a handle assembly, wherein the handle assembly comprises:
• (i) a housing associated with the first jaw, and
• (ii) an arm associated with the second jaw, wherein the arm is configured to move the second jaw between the open position and the closed position, wherein the arm is configured to move relative to the housing between a first position, a second position, and a third position, wherein the second position is interposed between the first position and the third position, wherein the electrode assembly is configured to activate in response to the arm reaching the third position;
• and
• (c) an arm engagement assembly comprising:
• (i) a resilient body comprising a first cam feature, and
• (ii) a detent associated with the arm, wherein the resilient body is configured to resiliently deform through engagement of the first cam feature with the detent as the arm transitions from the first position to the second position, wherein the resilient body and the detent are configured to cooperate to inhibit the arm from moving from the second position toward the first position.

A surgical instrument comprising:

• (a) an end effector, wherein the end effector comprises:
• (i) a first jaw,
• (ii) a second jaw coupled with the first jaw, wherein the second jaw is operable to move between an open position and a closed position, and
• (iii) an electrode assembly;
• (b) a handle assembly, wherein the handle assembly comprises:
• (i) a housing associated with the first jaw, and
• (ii) a resilient arm associated with the second jaw, wherein the resilient arm is configured to move the second jaw between the open position and the closed position, wherein the resilient arm is configured to move relative to the housing between a first position, a second position, and a third position, wherein the resilient arm is configured to flex while in the second position and the third position such that the second jaw remains in the closed position while the resilient arm is in both the second position and the third position;
• and
• (c) an arm engagement assembly comprising:
• (i) a resilient body comprising a first cam feature, and
• (ii) a detent configured to engage the first cam feature and thereby deform the resilient body as the arm transitions from the first position to the second position, wherein the resilient body is further configured to engage the detent after the arm reaches the second position to thereby inhibit the arm from moving from the second position toward the first position.