LOCKOUT DISABLING MECHANISM

[0001] This application is related to Application Docket No. END7522USNP/140427 titled “SIMULTANEOUS I-BEAM AND SPRING DRIVEN CAM JAW CLOSURE MECHANISM,” filed concurrently herewith and Application Docket No. END7537USNP/140430 titled “ELECTROSURGICAL ELECTRODE MECHANISM,” filed concurrently herewith; each of which is incorporated herein by reference in its entirety.

[0002] The present disclosure is related generally to electrosurgical devices with various mechanisms for clamping and treating tissue. In particular, the present disclosure is related to electrosurgical devices with a knife lockout disabling feature.

[0003] Conventional electrosurgical devices have a knife lockout that prevents the user from firing the knife unless the energy is activated. The energy button and lockout button are the same component. This feature, however, prevents a user of a conventional electrosurgical device from turning off or otherwise disabling the knife lockout feature such that the device can be operated faster. Also, conventional electrosurgical devices make it difficult to unlock the knife when the fire trigger is forced to the closed position. Thus, when the knife eventually comes unlocked, the knife jumps forward due to the potential energy developed under the compressive forces. Such jump of the knife is undesirable. Accordingly, to provide flexibility to a user of a conventional electrosurgical device, the following disclosure describes various solutions for turning off the knife lockout.

[0004] While several devices have been made and used, it is believed that no one prior to the inventors has made or used the device described in the appended claims.

[0005] In one embodiment, a surgical instrument is provided. The surgical instrument comprises a handle assembly. The handle assembly comprises a trigger operatively coupled to a firing plate; an energy button configured to deliver energy to at least one electrode; a lockout element operatively coupled to the energy button, the lockout element configured to prevent operation of the firing plate; and a lockout disabling mechanism configured to disable the lockout element, the lockout disabling mechanism operable between a first position and a second position, wherein when the lockout disabling mechanism is located in the first position, the lockout element is enabled and can be unlocked by the energy button, and wherein when the lockout disabling mechanism is in the second position, the lockout element is disabled.

[0006] In another embodiment, the lockout disabling mechanism of the surgical instrument comprises a button slidably movable between the first position and the second position; a slider operatively coupled to the button, wherein the slider is slidably movable between the first position and the second position by the button; and a lever arm having a first end and a second end, the first end coupled to the slider and the second end coupled to the lockout element. The lever arm disables the lockout element when the slider is slidably moved from the first position to the second position.

[0007] In various other embodiments, the lockout disabling mechanism of the surgical instrument comprises a lock arm operatively coupled to the lever arm and the lockout element. The slider of the surgical instrument comprises a ramped wall portion to engage the first end of the lever arm. The slider of the surgical instrument comprises a detent to provide tactile feedback when locking and unlocking the lockout disabling mechanism. The detent is configured to maintain the slider in the locked position.

[0008] In another embodiment, the lockout disabling mechanism of the surgical instrument comprises a button rotatably movable between the first position and the second position; a rotator operatively coupled to the button, wherein the rotator is rotatably movable between the first position and the second position by the button; and a lever arm having a first end and a second end, the first end coupled to the rotator and the second end coupled to the lockout element; wherein the lever arm disables the lockout element when the rotator is rotatably moved from the first position to the second position. The lockout disabling mechanism of the surgical instrument comprises a lock arm operatively coupled to the lever arm and the lockout element.

[0009] In one embodiment, a surgical instrument is provided. The surgical instrument comprises a handle assembly. The handle comprises a trigger operatively coupled to a trigger plate and a firing plate; an energy button configured to deliver energy to at least one electrode; a lockout element operatively coupled to the energy button, the lockout element configured to prevent operation of the firing plate; and a lockout disabling mechanism configured to disable the lockout element, the lockout disabling mechanism operable between a first position and a second position, wherein when the lockout disabling mechanism is located in the first position, the lockout element is enabled and can be unlocked by the energy button, and wherein when the lockout disabling mechanism is in the second position, the lockout element is disabled; a shaft assembly comprising a proximal end and a distal end, wherein the shaft assembly is coupled to the handle assembly at the proximal end; and an end effector coupled to the distal end of the shaft assembly. The end effector comprises a jaw assembly. The jaw assembly comprises a first jaw member; and a second jaw member, wherein rotation of the trigger plate transitions the jaw assembly between an open configuration and an approximated configuration by moving at least one of the first jaw member and the second jaw member relative to the other one of the first jaw member and the second jaw member; and a cutting member deployable in response to rotation of the firing plate.

[0010] In another embodiment, the lockout disabling mechanism of the surgical instrument comprises a button slidably movable between the first position and the second position; a slider operatively coupled to the button, wherein the slider is slidably movable between the first position and the second position by the button; and a lever arm having a first end and a second end, the first end coupled to the slider and the second end coupled to the lockout element; wherein the lever arm disables the lockout element when the slider is slidably moved from the first position to the second position.

[0011] In another embodiment, the lockout disabling mechanism of the surgical instrument comprises a lock arm operatively coupled to the lever arm and the lockout element. The slider of the surgical instrument comprises a ramped wall portion to engage the first end of the lever arm. The slider of the surgical instrument comprises a detent to provide tactile feedback when locking and unlocking the lockout disabling mechanism. The detent of the surgical instrument is configured to maintain the slider in the locked position.

[0012] In another embodiment, the lockout disabling mechanism surgical instrument comprises a button rotatably movable between the first position and the second position; a rotator operatively coupled to the button, wherein the rotator is rotatably movable between the first position and the second position by the button; and a lever arm having a first end and a second end, the first end coupled to the rotator and the second end coupled to the lockout element. The lever arm disables the lockout element when the rotator is rotatably moved from the first position to the second position. The lockout disabling mechanism of the surgical instrument comprises a lock arm operatively coupled to the lever arm and the lockout element.

[0013] In one embodiment, a surgical instrument is provided. The surgical instrument comprises an energy button; a lockout mechanism configured to prevent a cutting element from being fired unless the energy button is actuated; and a lockout disabling mechanism configured to disable the lockout mechanism, the lockout disabling mechanism is configured to operate between a first position and a second position, wherein when the lockout disabling mechanism is located in the first position, the lockout mechanism is enabled, and wherein when the lockout disabling mechanism is in the second position, the lockout mechanism is disabled.

[0014] In another embodiment, the lockout disabling mechanism of the surgical instrument comprises a button slidably movable between the first position and the second position; a slider operatively coupled to the button, wherein the slider is slidably movable between the first position and the second position by the button; and a lever arm having a first end and a second end, the first end coupled to the slider and the second end coupled to the lockout element. The lever arm disables the lockout element when the slider is slidably moved from the first position to the second position. The lockout disabling mechanism comprises a lock arm operatively coupled to the lever arm and the lockout element. The slider comprises a ramped wall portion to engage the first end of the lever arm. The slider comprises a detent to provide tactile feedback when locking and unlocking the lockout disabling mechanism. The detent is configured to maintain the slider in the locked position.

[0015] In another embodiment, the lockout disabling mechanism of the surgical instrument comprises a button rotatably movable between the first position and the second position; a rotator operatively coupled to the button, wherein the rotator is rotatably movable between the first position and the second position by the button; and a lever arm having a first end and a second end, the first end coupled to the rotator and the second end coupled to the lockout element. The lever arm disables the lockout element when the rotator is rotatably moved from the first position to the second position.

[0016] The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.

[0067] In the following detailed description, reference is made to the accompanying drawings, which form a part hereof. In the drawings, similar symbols and reference characters typically identify similar components throughout the several views, unless context dictates otherwise. The illustrative embodiments described in the detailed description, drawings, and claims are not meant to be limiting. Other embodiments may be utilized, and other changes may be made, without departing from the scope of the subject matter presented here.

[0068] The following description of certain examples of the technology should not be used to limit its scope. Other examples, features, aspects, embodiments, and advantages of the technology will become apparent to those skilled in the art from the following description, which is by way of illustration, one of the best modes contemplated for carrying out the technology. As will be realized, the technology described herein is capable of other different and obvious aspects, all without departing from the technology. Accordingly, the drawings and descriptions should be regarded as illustrative in nature and not restrictive.

[0069] It is further understood that any one or more of the teachings, expressions, embodiments, examples, etc. described herein may be combined with any one or more of the other teachings, expressions, embodiments, examples, etc. that are described herein. The following-described teachings, expressions, embodiments, examples, etc. should therefore not be viewed in isolation relative to each other. Various suitable ways in which the teachings herein may be combined will be readily apparent to those of ordinary skill in the art in view of the teachings herein. Such modifications and variations are intended to be included within the scope of the claims.

[0070] Before explaining the various embodiments of the surgical devices having a knife lockout disabling mechanism in detail, it should be noted that the various embodiments disclosed herein are not limited in their application or use to the details of construction and arrangement of parts illustrated in the accompanying drawings and description. Rather, the disclosed embodiments may be positioned or incorporated in other embodiments, variations and modifications thereof, and may be practiced or carried out in various ways. Accordingly, embodiments of the surgical devices disclosed herein are illustrative in nature and are not meant to limit the scope or application thereof. Furthermore, unless otherwise indicated, the terms and expressions employed herein have been chosen for the purpose of describing the embodiments for the convenience of the reader and are not to limit the scope thereof. In addition, it should be understood that any one or more of the disclosed embodiments, expressions of embodiments, and/or examples thereof, can be combined with any one or more of the other disclosed embodiments, expressions of embodiments, and/or examples thereof, without limitation.

[0071] Also, in the following description, it is to be understood that terms such as front, back, inside, outside, top, bottom and the like are words of convenience and are not to be construed as limiting terms. Terminology used herein is not meant to be limiting insofar as devices described herein, or portions thereof, may be attached or utilized in other orientations. The various embodiments will be described in more detail with reference to the drawings.

[0072] In various embodiments, the present disclosure provides an electrosurgical instrument comprising a knife lockout disabling mechanism configured to disable or override the knife lockout mechanism of the electrosurgical instrument. In one embodiment, the knife lockout disabling mechanism comprises a slider, a lever arm, and a button operatively coupled to the slider. The button can be engaged by the user to slidably move the slider back (proximally) and forth (distally) between several positions. In one embodiment, the slider is configured to slidably move back and forth between two positions. The lever arm is configured to pivot around a lock arm and to push in or activate the energy button when rotated. In one embodiment, the lever arm is connected to a ramped (or pivoting) slider that forces the lever arm to rotate and force the lock arm to rotate to unlock, disable, or override the knife lockout mechanism of the electrosurgical instrument. In one embodiment, the slider includes features to lock the lever arm in place once it is activated. A spring may be coupled to the energy button to force the lever arm and the slider back to their start positions once the energy button is deactivated. In other words, in one embodiment, the slider is configured to be in the lock-off (lock defeated) or lock-on (lock undefeated) position and the spring is configured to force the slider back to its start position in the transition area.

[0073] In another embodiment, the knife lockout disabling mechanism of the electrosurgical instrument comprises a rotator, a lever arm, and a button operatively coupled to the rotator configured to disable, override, or otherwise turn off the knife lockout mechanism of the electrosurgical instrument. The button can be engaged by the user to rotate the rotator between various positions. In one embodiment, the rotator can be rotated between two positions. The rotator acts on the lever arm to engage a surface of the lockout mechanism and thereby defeat the lockout mechanism of the electrosurgical instrument.

[0074] The above knife lockout disabling mechanisms, as discussed in more detail below, provide several advantages over conventional electrosurgical devices with knife lockout mechanisms that cannot be disabled. For example, the lockout disabling mechanisms according to the present disclosure are configured to fit in a form factor of current electrosurgical instruments with only a change to one of the housing shrouds. The lockout disabling mechanism generally moves between two states (off or on). Thus, the button portion of the slider or rotator can move slidably or rotatably between the two positions or states but not in any intermediate positions between the two states. In one embodiment, the button can be retrofitted into some existing electrosurgical instruments and locks into place without requiring any additional or new components to lock it in position. The button can be configured to employ a spring that is already provided for the energy button, as described herein. Also, either the slider or rotator is operatively coupled to the energy button such that when the knife lockout disabling mechanism is activated, it moves the energy button inward to provide a visual and tactile clue that the knife lockout feature is turned off.

[0075] Turning now to the figures, FIG. 1 illustrates a surgical instrument 102 comprising a trigger assembly 107 and a lockout disabling mechanism 108. In this view, a first jaw member 116a of an end effector 110 is fully open and the knife lockout disabling mechanism 108 is located in the off position. The knife lockout disabling mechanism 108 is configured to clamp and fire an end effector 110 coupled to the surgical instrument 102. The surgical instrument 102 comprises a handle assembly 104, a shaft assembly 112, and the end effector 110. The shaft assembly 112 comprises a proximal end and a distal end. The proximal end of the shaft assembly 112 is coupled to the distal end of the handle assembly 104. The end effector 110 is coupled to the distal end of the shaft assembly 112. The handle assembly 104 comprises a pistol grip 118. The handle assembly 104 comprises a left handle housing shroud 106a and a right handle housing shroud 106b. The trigger assembly 107 comprises a trigger 109 actuatable towards the pistol grip 118. The knife lockout disabling mechanism 108 comprises a button 139, or knob, that is actuatable for adjusting or controlling the position of the knife lockout disabling mechanism 108 between first and second positions A and B (A=Distal and B=Proximal relative to the clinician) within a slot 111 formed in the left handle housing shroud 106a. A rotatable shaft knob 120 is configured to rotate the shaft assembly 112 with respect to the handle assembly 104. The handle assembly 104 further comprises an energy button 122 configured to provide electrosurgical energy to one or more electrodes in the end effector 110.

[0076] The knife lockout mechanism forces the user to first clamp (close the jaws 110), energize the electrodes, and then cut the tissue (fire the knife). The knife unlock feature contains the energy button 122 so that the energy button 122 has to be depressed before the knife can be released or that the single trigger can move the rack 136 forward. The single trigger 109 closes the jaws in the first ˜13 degrees of stroke. The single trigger 109 fires the knife in the last ˜29 degrees of stroke. The lockout is the stop in between the first stroke and the second stroke. As shown in FIG. 48, an energy button 166 is located underneath the energy button 122 housing to illustrate that the lock release mechanism also is the energy delivery element.

[0077] The shaft assembly 112 comprises a closure/jaw actuator, a firing/cutting member actuator, and an outer sheath. In some embodiments, the outer sheath comprises the closure actuator. The outer sheath comprises one or more contact electrodes on a distal end configured to interface with the end effector 110. The one or more contact electrodes are operatively coupled to the energy button 122 and an energy source (not shown).

[0078] The energy source may be suitable for therapeutic tissue treatment, tissue cauterization/sealing, as well as sub-therapeutic treatment and measurement. The energy button 122 controls the delivery of energy to the electrodes. As used throughout this disclosure, a button refers to a switch mechanism for controlling some aspect of a machine or a process. The buttons may be made out of a hard material such as usually plastic or metal. The surface may be formed or shaped to accommodate the human finger or hand, so as to be easily depressed or pushed. Buttons can be most often biased switches, even though many un-biased buttons (due to their physical nature) require a spring to return to their un-pushed state. Terms for the “pushing” of the button, may include press, depress, mash, and punch.

[0079] In some embodiments, an end effector 110 is coupled to the distal end of the shaft assembly 112. The end effector 110 comprises a first jaw member 116a and a second jaw member 116b. The first jaw member 116a is pivotally coupled to the second jaw member 116b. The first jaw member 116a is pivotally moveable with respect to the second jaw member 116b to grasp tissue therebetween. In some embodiments, the second jaw member 116b is fixed. In other embodiments, the first jaw member 116a and the second jaw member 116b are pivotally movable. The end effector 110 comprises at least one electrode. The electrode is configured to deliver energy. Energy delivered by the electrode may comprise, for example, radiofrequency (RF) energy, sub-therapeutic RF energy, ultrasonic energy, and/or other suitable forms of energy. In some embodiments, a cutting member (not shown) is receivable within a longitudinal slot defined by the first jaw member 116a and/or the second jaw member 116b. The cutting member is configured to cut tissue grasped between the first jaw member 116a and the second jaw member 116b. In some embodiments, the cutting member comprises an electrode for delivering energy, such as, for example, RF and/or ultrasonic energy.

[0080] In certain instances, as described above, the surgical instrument 102 may include an automatic energy lockout mechanism. The energy lockout mechanism can be associated with a closure mechanism of the surgical instrument 102. In certain instances, the energy lockout mechanism can be configured to permit energy delivery to the end effector 10 when the energy delivery button 122 is actuated if the jaw members 116a and 116b are in an open configuration. In certain instances, the energy lockout mechanism may be configured to deny energy delivery to the end effector 110 when the energy delivery button 122 is actuated if the jaw members 116a and 116b are in a closed configuration. In certain instances, the energy lockout mechanism automatically transitions from permitting the energy delivery to denying the energy delivery when the jaw members 116a and 116b are transitioned from the closed configuration to the open configuration, for example. In certain instances, the energy lockout mechanism automatically transitions from denying the energy delivery to permitting the energy delivery when the jaw members 116a and 116b are transitioned from the open configuration to the closed configuration, for example.

[0081] FIG. 2 is a perspective view of a handle assembly 104 of a surgical instrument 102 illustrated in FIG. 1, according to one embodiment, with the right housing shroud 106a and the outer and inner sheaths of the shaft assembly 112 removed to show some of the internal mechanisms. The left handle housing shroud 106b of the handle assembly 104 comprises the knife lockout disabling mechanism 108. The button 139 is located in the first “off” position A (A=distal relative to the clinician) within the slot 111 formed in the right handle housing shroud 106a. In the illustrated embodiment, position B (B=proximal relative to the clinician) corresponds to the second “on” position of the knife lockout disabling mechanism 108, where the knife lockout mechanism remains disabled until the button is switched back to position A. Accordingly, position A corresponds to the enabled state of the knife lockout mechanism and position B corresponds to the disabled state of the knife lockout mechanism. Stated differently, position A corresponds to the “off” state of the knife lockout disabling mechanism 108 and position B corresponds to the “on” state of the knife lockout disabling mechanism 108. When the knife lockout mechanism is in the disabled state, the energy button 122 may appear to be depressed to provide a visual indication to the clinician that the knife lockout mechanism has been disabled but without energizing the electrodes in the end effector 110 (FIG. 1). When the knife lockout mechanism is disabled, the knife may be fired at will without the need to apply electrosurgical energy to one or more electrodes in the end effector 110.

[0082] The trigger assembly 107 comprises the necessary components for closing the jaw members 116a, 116b and firing the cutting member or knife bands 142. The trigger assembly 107 comprises a trigger plate 124 and firing plate 128 operatively coupled to the trigger 109. Squeezing the trigger 109 in direction C towards the pistol grip 118 rotates the trigger plate 124 which operates the toggle clamp 145 to advance a yoke 132 and a closure actuator 123 distally to close the jaw members 116a, 116b of the end effector. Initial rotation of the trigger plate 124 also slightly rotates the firing plate 128. The firing plate 128 comprises a sector gear with a plurality of teeth 131 that engage and rotate a first pinion gear 133, which engages a second pinion gear 134 to advance a rack 136 (neither is shown in this view). A lock arm 157 (shown in FIGS. 22-24, 28, 32, 35, 38, 41, 44, for example) is operatively coupled to a lever arm 115, an unlock arm 119, and a lockout element 165. When the instrument 102 is in normal lockout mode, the lock arm 157 engages a notch 158 (shown in FIGS. 23-25, 38, 41, 44, and 45, for example) in the rack 136 to lock the rack 136 and prevent the rack 136 from moving distally (firing) no matter how hard the trigger 109 is squeezed.

[0083] The single trigger 109 closes the jaws in the first ˜13 degrees of stroke. The trigger plate 24 is configured to interface with the trigger plate 124 during rotation of the trigger 109 from an initial position to a first rotation, which is ˜13 degrees of stroke, for example. The trigger plate 124 is operably coupled to the firing plate 128. In certain instances, the firing plate 128 may include a first slot 128a and a second slot 128b. The first slot 128a receives a drive pin 148 fixedly coupled to the trigger plate 124. The pin 148 slidably moves within the first slot 128a. Rotation of the trigger plate 124, while the pin 148 is slidably received within the first slot 128a, drives rotation of the firing plate 128. The teeth 131 of the sector gear engage and rotate the first pinion 133, which in turn drives the second pinion 134, which drives the rack 136 distally to fire the cutting element, or knife, but only when the knife lockout is unlocked, released, or disabled.

[0084] The single trigger 109 fires the knife in the last ˜29 degrees of stroke. Rotation of the trigger plate 124 beyond a predetermined rotation such as, for example, the first rotation, causes rotation of the firing plate 128. Rotation of the firing plate 128 deploys a cutting member within the end effector 110. For example, in the illustrated embodiment, the firing plate 128 comprises a sector gear operably coupled to a rack 136 through the first and second pinions 133, 134. The firing plate 128 comprises a plurality of teeth 131 configured to interface with the first pinion 133. Rotation of the firing plate 128 rotates the first and second pinions 133, 134, to drive the rack 136 distally. Distal movement of the rack 136 drives the cutting member actuator distally, causing deployment of the cutting member (e.g., knife) within the end effector 110.

[0085] The lockout is the stop in between the first stroke and the second stroke. Turning back now to the description of the lockout disabling mechanism 108, when the slider 113 button 139 portion is in located in position A, the lock arm 157 cam be released by pressing or actuating the energy button 122 to rotate the lockout element 165, which rotates the unlock arm 119 to release the lock arm 157. Once the lock arm 157 is released, the rack 136 is enabled to advance distally and fire the knife by squeezing the trigger 109 in direction C further towards the pistol grip 118. As the trigger 109 is squeezed, the firing plate 128 rotates and drives the first pinion gear 133, which drives the second pinion gear 134 to drive the rack 136.

[0086] When the slider 113 button 139 is located in position B, the slider 113 rotates the lever arm 115, which rotates the unlock arm 119 to releases the lock arm 157. While the button 139 is in position B, the rack 136 can be fired without the need to press energy button 122 to rotate the lockout element 165. A detent may be provided to hold the button in either position A or B. These and other features are described in more detail hereinbelow.

[0087] The shaft assembly 112 comprises a closure/jaw actuator and a firing/cutting member actuator. The closure/jaw actuator comprises a yoke 132 and toggle clamp 145 assembly operatively coupled to a closure actuator 112 which acts on a closure spring 114 coupled to a spring-to-bar interface element 127 and a closure bar 116. In one instance the closure bar 116 is operatively coupled to the jaw members 116a, 116b via at least one linkage. The firing/cutting member actuator comprises a rack 136 operatively coupled to a firing bar 117, which is slidably received within the closure actuator 112 and the closure spring 114. The firing bar 117 is coupled to a knife pusher block 140 and a flexible I-beam knife band 142 comprising multiple flexible bands fastened together and a cutting element at the distal end. Advancing the rack 136 in the distal direction advances the cutting element band 142 distally through a channel or slot formed in the jaw members 116a, 116b.

[0088] FIG. 3 is a side elevation view of a handle assembly 4 of a surgical instrument 2 similar to the surgical instrument 102 shown in FIGS. 1 and 2, with the left handle housing shroud removed to expose various mechanisms located within the handle assembly 4 and the knife lockout mechanism enabled. The handle assembly 4 comprises a plurality of components for actuating the surgical instrument 2, such as, for example, mechanism for affecting the closure of the jaw members of the end effector, deploying a cutting member (e.g., knife) within the end effector, and/or delivering energy to one or more electrodes coupled to the end effector. The knife lockout disabling mechanism 8 is configured to disable the knife lockout mechanism of the end effector. The knife lockout disabling mechanism 8 comprises a slider 13, a lever arm 15, and a button 39 operatively coupled to the slider 13. An unlock arm 19 is actuated by the lever arm 15 as the slider 13 is slidably translated from the first position A to the second position B as indicated in FIG. 4. While the slider 13 translates in a proximal direction B, a ramped or angled wall 49 formed within a body 43 portion of the slider 13 engages or contacts one end 51 of the lever arm 15 causing the lever arm 15 to rotate in a first direction E about a pivot point 59. The rotating lever arm 15 pushes the unlock arm 19 causing the unlock arm 19 to rotate in the same first direction. One end of the unlock arm 19 rotates the knife lockout element 65 in a second, opposite, direction and the other end of the unlock arm 19 rotates the lock arm 57 (not shown in this view, but shown in FIGS. 8 and 9) to unlock or disable the knife lockout function.

[0089] FIG. 4 is a side elevation view of the handle assembly 4 of the surgical instrument 2 shown in FIG. 3, with the left handle housing shroud removed to expose various mechanisms located within the handle assembly 4 and the knife lockout mechanism disabled, according to one embodiment. As shown in FIG. 4, the slider 13 has been slidably translated to the proximal position as indicated by arrow D. The lever arm 15 and the unlock arm 19 have been rotated in a the direction indicated by arrow G by the other end 53 of the lever arm 15 and the knife lockout element 65 has been rotated in a second, opposite, direction. The unlock arm 19 acts on the lock arm 57 to disable the knife lockout function. The energy button 22 is operatively coupled to the unlock arm 19. Thus, the energy button 22 will be in a depressed state as indicated by arrow F when the knife lockout element 65 has been disabled.

[0090] FIG. 5 is a perspective view of the handle assembly 4 of the surgical instrument 2 shown in FIG. 4, with the left handle housing shroud removed to expose various mechanisms located within the handle assembly 4 and the knife lockout element 65 disabled, according to one embodiment. In various embodiments, the electrosurgical instrument 2 comprising a knife lockout disabling mechanism 8 configured to disable or override the knife lockout element 65 of the electrosurgical instrument 2. As shown win FIG. 5, the slider 13 has been slidably translated proximally in direction B to disable the knife lockout element 65 as described in connection with FIG. 4. The button 39 can be engaged by the clinician to slidably move the slider 13 back (proximally) and forth (distally) between several positions. In one embodiment, the slider 13 is configured to slidably move back and forth between the first and second positions A and B. The lever arm 15 is configured to pivot about the unlock arm 19 and to push in the energy button 22 when rotated. In one embodiment, the lever arm 15 is coupled to a ramped (or pivoting) slider 13 that forces the lever arm 15 to rotate in a first direction and force the unlock arm 19 to rotate in a second, opposite, direction. The unlock arm 19 rotates the lock arm 57 to unlock, disable, or override the knife lockout mechanism of the electrosurgical instrument 2. In one embodiment, the slider 13 includes features to lock the lever arm 15 in place once it is activated. A spring may be coupled to the energy button 22 to force the lever arm 15 and the slider 13 back to their start positions A or B once the energy button 22 is deactivated. In other words, in one embodiment, the slider 13 may be configured to be in the lock-OFF (lock defeated, disabled, etc.) or lock-ON (lock undefeated, enabled, etc.) position and the spring is configured to force the slider 13 back to its start position in the transition area. A longitudinal projection 41 extends distally from the body 43 of the slider 13.

[0091] Turning now to FIGS. 3-5, the knife lockout disabling mechanism 8 is coupled to one or more mechanisms for closing the jaw members of the end effector and deploying a cutting member (e.g., knife) therein. In one embodiment, when the trigger 9 is squeezed in direction C towards the pistol grip 18, the trigger 9 rotates the trigger plate 24 about a rotation point defined by a rotation pin 25a. Rotation of the trigger plate 24 to a first position causes a toggle clamp 45 to advance a yoke 32 and a closure actuator configured to transition the jaw members from an open position to a closed position. For example, in the illustrated embodiment, the toggle clamp 45 is operatively coupled to a yoke 32. The toggle clamp 45 is movably coupled to the trigger plate 24. Rotation of the trigger plate 24 also drives the yoke 32 distally. Distal movement of the yoke 32 compresses a closure spring 114, causing distal movement of the closure actuator. As previously discussed in connection with FIGS. 1 and 2, distal movement of the closure actuator compresses a closure spring. The closure spring is coupled to a closure bar via the spring-to-bar interface element. Accordingly, distal movement of the closure actuator causes the closure bar to pivotally move the first jaw member from an open position to a closed position with respect to the second jaw member, for example.

[0092] Rotation of the trigger plate 24 beyond a predetermined rotation such as, for example, the first rotation position, causes partial rotation of the firing plate 28. Rotation of the firing plate 28 deploys a cutting member within the end effector 10. For example, in the illustrated embodiment, the firing plate 28 comprises a sector gear operably coupled to a rack 36 through first and second pinions 33 and 34. The sector gear of the firing plate 28 comprises a plurality of teeth 31 configured to interface with the first pinion 33. The first pinion 33 drives the second pinion 34. Thus, rotation of the firing plate 28 rotates the pinions 33 and 34, driving the rack 36 distally. Distal movement of the rack 36 drives the cutting member actuator distally, causing deployment of the cutting member (e.g., knife) within the end effector 10. The rack 36, however, comprises at least one notch 58 configured to engage the lock arm 57. When the lock arm 57 engages the notch 58 in the rack 36, the rack 36 is prevented from firing distally. This is referred to as the lockout state. When the button 39 in position A, the energy button 22 must be depressed inwardly towards to pistol grip 18 to unlock the lock arm 57 and release the rack 36. A spring is provided behind the energy button 22 to balance out this force. When the button 39 in position B, the lockout mechanism is disabled by the lever arm 15 and the unlock arm 19 releasing the lock arm 57.

[0093] The trigger plate 24 is configured to interface with the toggle clamp 45 during rotation of the trigger 9 from an initial position to a first rotation position, for example. The trigger plate 24 is operably coupled to the firing plate 28. In certain instances, the firing plate 28 may include a first slot 28a and a second slot 28b. The first slot 28a receives a drive pin 48 coupled to the trigger plate 24. The drive pin 48 is slidably driven by the trigger plate 24 in the first slot 28a and drives the firing plate 28.

[0094] Rotation of the firing plate 28 by the drive pin 48 in the first slot 28a rotates the sector gear teeth 31, which engage and rotate the first pinion 33. The first pinion 33 rotates the second pinion 34. The second pinion 34 drives the rack 36 distally to fire the cutting element (e.g., knife), but only when the lock arm 57 is released or disabled from the notch 58 in the rack 32 either by locating the button 39 in position B or pressing the energy button 22 to release the lockout element 65.

[0095] FIG. 6 illustrates a detailed view of the knife lockout disabling mechanism 8 showing the slider 13, one end of the lever arm 15, and the button 39, according to one embodiment. The slider 13 comprises a body 43 defining a longitudinal slot 47 enabling the slider 13 to slidably translate in either direction A or B. In FIG. 6, the slider 13 is shown in the proximal position B, wherein the lock arm 57 is disabled allowing the rack 32 to move distally to drive the firing bar. A projection 41 extends longitudinally from the body 43 of the slider 13. At the distal end of the projection 41, a detent 21 feature provides tactile feedback to the clinician when locking and unlocking the knife lockout mechanism. The detent 21 feature also keeps the slider 13 in the unlocked position like a detent. An angled wall 49 (ramp) portion of the body 43 engages one end 51 of the lever arm 15.

[0096] FIG. 7 is an exploded view of the handle assembly 4 with the right handle housing shroud and various mechanisms located within the handle assembly 4 removed to more clearly show the components of the knife lockout disabling mechanism 8, according to one embodiment. As shown in FIG. 6, the slider 13 comprises a longitudinal slot 47 that is slidably movable over a longitudinal projection 60 formed on the left handle housing shroud 6a. The slot 11 provides an aperture for the button 39, operatively coupled to the slider 13, to slidably move between first and second positions (A and B). One end 53 of the lever arm 15 is pivotally mounted to a pivot point 27 formed on the left handle housing shroud 6a. Another end 51 of the lever arm 15 is received in a space 29 defined by the slider 13 body 43 and engages the ramp 49 when the slider is in position A.

[0097] FIGS. 8 and 9 are perspective views of the handle assembly 4 with the right handle housing shroud and various mechanisms located within the handle assembly 4 removed to more clearly show the components of the knife lockout disabling mechanism 8, according to one embodiment. As shown in FIG. 8, the knife lockout disabling mechanism 8 is in the locked state. The slider 13 is located in position A and one end of the lever arm 15 is abutting the ramp 49 wall formed in the slider 13 body 43. The ramp 49 engages one end 53 of the lever arm 15 to pivotally rotate the lever arm 15 as the slider 13 moves from position A, shown in FIG. 8, to position B, shown in FIG. 9. The lever arm 15 is configured to pivot the unlock arm 19 such that one end of the unlock arm 19 pushes in the energy button 22 when rotated as shown in FIG. 9 and the other end of the unlock arm 19 release the lock arm 57 to disable the knife lockout mechanism. As shown in FIG. 8, the lockout element 65 is shown in the locked position such that the lock arm 57 engages the notch 58 formed in the rack 32 to prevent the knife from firing. As shown in FIG. 9, when the unlock arm 19 is rotated in the second, opposite, direction, the lock arm 57 unlocks the knife lockout function to enable firing of the knife without actuating the energy button 22. Nevertheless, the energy button 22 is slightly pushed in to provide an indication that the lockout function has been disabled.

[0098] FIGS. 10-15 illustrate a knife lockout disabling mechanism according to another embodiment. FIG. 10 is a side elevation view of the handle assembly 104 of a surgical instrument 102, with the left handle housing shroud 106a removed to expose various mechanisms located within the handle assembly 104 and the knife lockout disabling mechanism 108 in the “off” position, according to one embodiment. The knife lockout disabling mechanism 108 comprises a slider 113, a button 139, and a lever arm 115. The slider 113 comprises a body 143 defining a longitudinal slot 147 wherein the slider 113 slidably translates in directions A and B by sliding the button 139. The slider 113 further comprises longitudinally extending projections 141, 163, where the second longitudinal projection 163 and the body 143 define a cutout portion 162. A ramped or angled wall 149 engages the end 153 of the lever arm 115. Thus, when the slider 113 moves from position A to position B, the ramp 149 engages the one end 153 of the lever arm 115 causing it to rotate in a first direction. The rotation of the lever arm 115 in the first direction causes one end of the unlock arm 119 to rotate in the same first direction to push on the knife lockout element 165 and the other end of the unlock arm 119 disengages the lock arm 157 (shown in FIGS. 22-24, 28, 32, 35, 38, 41, 44, for example) from the notch 158 (shown in FIGS. 23-25, 38, 41, 44, and 45, for example) in the rack 132. When the lock arm 57 is rotated out of the notch 58 it unlocks or disables the knife lockout function, thus enabling the cutting element to be fired by the rack 132.

[0099] As shown in FIG. 10, a slider 113 portion of the knife lockout disabling mechanism 108 has been slidably translated to a distal position by sliding the button 139 in the distal direction A. A lever arm 115 is configured to rotate in a first direction as indicated by arrow E when the slider 113 is slidably translated in the proximal direction B as indicated by arrow B. A unlock arm 119 is configured to rotate in the same first direction when one end 153 of the lever arm 115 pushes on the unlock arm 119 as the slider 113 is slidably translated in the proximal direction B. One end of the unlock arm 119 pushes on the knife lockout element 165 to cause it to rotate in an opposite second direction and the other end of the unlock arm 119 unlocks the lock arm 57 to disable the knife lockout function. The energy button 122 is operatively coupled to the unlock arm 119 and is shown in an undepressed state to show that the knife lockout mechanism is enabled.

[0100] FIG. 11 is a perspective view of the handle assembly 104 of the surgical instrument 102 shown in FIG. 10, with the left handle housing shroud 106a removed to expose various mechanisms located within the handle assembly 104 and the knife lockout mechanism disabled, according to one embodiment. In various embodiments, the electrosurgical instrument 102 comprising a knife lockout disabling mechanism 108 configured to disable or override the knife lockout mechanism of the electrosurgical instrument 102. As shown win FIG. 11, the slider 113 is still in the distal position A such that the knife lockout mechanism is enabled as described in connection with FIG. 10. The button 139 can be engaged by the clinician to slidably move the slider 113 back (proximally) and forth (distally) between several positions. In one embodiment, the slider 113 is configured to slidably move back and forth between the first and second positions A and B. The lever arm 115 is configured to pivot about the unlock arm 119 and to push in the energy button 122 when rotated. In one embodiment, the lever arm 115 is connected to a ramped (or pivoting) slider 113 that forces the lever arm 115 to rotate in a first direction and force the unlock arm 119 to rotate in a second, opposite, direction to unlock, disable, or override the knife lockout mechanism of the electrosurgical instrument 102. In one embodiment, the slider 113 includes features to lock the lever arm 115 in place once it is activated. A spring may be coupled to the energy button 122 to force the lever arm 115 and the slider 113 back to their start positions A or B once the energy button 122 is deactivated. In other words, in one embodiment, the slider 113 is configured to be in the lock-off (lock defeated) or lock-on (lock undefeated) position and the spring is configured to force the slider 113 back to its start position in the transition area. A longitudinal projection 141 extends distally from the body 143 of the slider 113.

[0101] FIGS. 12 and 6B are detailed views of the knife lockout disabling mechanism 108 showing the slider 113, one end of the lever arm 115, and the button 139, according to one embodiment. The slider 113 comprises a body 143 defining a first longitudinal slot 147 that enables the slider 113 to slidably translate proximally and distally. A projection 141 extends longitudinally from the body 143 of the slider 113. At the distal end of the projection 141, a detent 121 feature provides tactile feedback to the clinician when locking and unlocking the knife lockout mechanism. The detent 121 feature also keeps the slider 113 in the unlocked position. An angled or ramped wall 149 portion of the body 143 engages one end 151 of the lever arm 115. A second longitudinal slot 160 and a cutout portion 162 defined by the second longitudinal projection 163 and the body 143 are provided on a proximal end of the slider 113.

[0102] As shown more particularly in FIG. 6B, the detent 121 is provided to the lock defeat OFF position so that the slider 113 will stay in place even when the lockout button 139 is pushed in. The detent 121 prevents the slider 113 from moving backwards when the energy button 122 is pressed to defeat the lockout. When the energy button 122 is depressed to defeat the lockout mechanism, the lockout defeat lever arm 115 moves with the energy button 122 and could cause the slider 113 to move freely with gravity or if the device is jolted. The detent 121 prevents the slider 113 from moving freely with gravity or if the device is jolted when the energy button 122 is depressed to defeat the lockout mechanism.

[0103] FIG. 13 is a side elevation view of the knife lockout disabling mechanism 108, according to one embodiment. The slider 113 is shown in the distal position corresponding to an enabled knife lockout mechanism. The button 139 is employed to slidably translate the slider 113 proximally and distally along the first longitudinal slot 147. The one end 151 of the lever arm 115 is shown resting on the ramped wall 149 portion of the slider 113 body 143. As shown, the lever arm 115 includes a notched portion 164 and defines a detent 121 to provide tactile feedback to the user regarding the state of the knife lockout mechanism. The lever arm 115 is rotatably coupled the unlock arm 119, which is rotatably coupled to the energy button 122.

[0104] FIGS. 14 and 15 provide additional views of the knife lockout disabling mechanism 108. FIG. 14 is a side elevational view of the surgical instrument 102 with the right handle housing shroud removed to expose various mechanisms located within the handle assembly 104 and the knife lockout mechanism enabled, according to one embodiment. FIG. 15 is a perspective view of the surgical instrument 102 with the right handle housing shroud removed to expose various mechanisms located within the handle assembly 104 and the knife lockout mechanism enabled, according to one embodiment.

[0105] With reference now to FIGS. 1, 2, 10, 11, 14, and 15, the knife lockout disabling mechanism 108 is coupled to one or more mechanisms for closing the jaw members 116a, 116b of the end effector 10 and deploying a cutting member (e.g., knife) therein. In one embodiment, when the trigger 109 is squeezed in direction C towards the pistol grip 118, the trigger 109 rotates the trigger plate 124 about a rotation point defined by a rotation pin 125a. Rotation of the trigger plate 124 to a first position causes a toggle clamp 145 to advance a yoke 132 and a closure actuator 112 configured to transition the jaw members 116a, 116b from an open position to a closed position. For example, in the illustrated embodiment, the toggle clamp 145 is operatively coupled to a yoke 132. The toggle clamp 145 is movably coupled to the trigger plate 124. Rotation of the trigger plate 124 also drives the yoke 132 distally. Distal movement of the yoke 132 compresses a closure spring 114, causing distal movement of the closure actuator 112. As previously discussed in connection with FIG. 2, distal movement of the closure actuator 112 compresses the closure spring 114. The closure spring 114 is coupled to the closure bar 116 via the spring-to-bar interface element 119. Accordingly, distal movement of the closure actuator 112 causes the closure bar 116 to pivotally move the first jaw member 16a from an open position to a closed position with respect to the second jaw member 16b, for example.

[0106] Rotation of the trigger plate 124 beyond a predetermined rotation such as, for example, the first rotation position, causes partial rotation of the firing plate 128. Rotation of the firing plate 128 deploys a cutting member within the end effector 110. For example, in the illustrated embodiment, the firing plate 128 comprises a sector gear operably coupled to a rack 136 through first and second pinions 133 and 134. The sector gear of the firing plate 128 comprises a plurality of teeth 131 configured to interface with the first pinion 133. The first pinion 133 drives the second pinion 134. Thus, rotation of the firing plate 128 rotates the first and second pinions 133 and 134 and drives the rack 136 distally. Distal movement of the rack 136 drives the cutting member actuator distally, causing deployment of the cutting member (e.g., knife) within the end effector 110. The rack 136, however, comprises at least one notch 58 configured to engage the lock arm 157. When the lock arm 157 engages the notch 58 in the rack 136, the rack 136 is prevented from firing distally. This is referred to as the lockout state. When the button 139 in position A, the energy button 122 must be depressed inwardly towards to pistol grip 118 to unlock the lock arm 57 and release the rack 136. When the button 139 in position B, the lockout mechanism is disabled by the lever arm 115 and the unlock arm 119 releasing the lock arm 157.

[0107] The trigger plate 124 is configured to interface with the toggle clamp 145 during rotation of the trigger 109 from an initial position to a first rotation position, for example. The trigger plate 124 is operably coupled to the firing plate 128. In certain instances, the firing plate 128 may include a first slot 128a and a second slot 128b. The first slot 128a receives a drive pin 148 coupled to the trigger plate 124. The drive pin 148 is slidably driven by the trigger plate 124 in the first slot 128a and drives the firing plate 128.

[0108] Rotation of the firing plate 128 by the drive pin 148 in the first slot 128a rotates the sector gear teeth 131 to rotate the first pinion 133. The first pinion 133 rotates the second pinion 134. The second pinion 134 drives the rack 136 distally to fire the cutting element (e.g., knife), but only when the lock arm 157 is released or disabled from the notch 158 in the rack 132 either by locating the button 139 in position B or pressing the energy button 122 to release the lockout element 165.

[0109] FIGS. 16 and 17 are side elevational views of a rotary knife lockout disabling mechanism 208 for a surgical instrument, according to one embodiment. FIG. 16 is a side elevational view of the rotary knife lockout disabling mechanism 208 for a surgical instrument where the knife lockout element 265 is enabled, according to one embodiment. FIG. 17 is a side elevational view of the rotary knife lockout disabling mechanism 208 for a surgical instrument where the knife lockout mechanism is disabled, according to one embodiment. As shown in FIGS. 16 and 17, in another embodiment, the knife lockout disabling mechanism 208 of the electrosurgical instrument 202 comprises a rotator 213, a lever arm 215, and a button 239 operatively coupled to the rotator 213 and is configured to disable, override, or otherwise turn off the knife lockout element 265 of the electrosurgical instrument 202. The button 239 can be engaged by the clinician to rotate the rotator 213 about a pivot point 247 between various positions. In one embodiment, the rotator 213 can be rotated about the pivot point 247 between two positions. The rotator 213 acts on the lever arm 215, which rotates a lock arm 219. The lock arm 219 rotates about a pivot point 259 and engages a surface of the lockout element 265 to rotate the lockout element 265 and thereby defeat the lockout mechanism of the electrosurgical instrument 202.

[0110] As shown in FIG. 16, the rotator 213 is positioned such that it can push on one end of the lever arm 215 when the rotator 213 is rotated in a first direction about the pivot point 247. The lever arm 215 and the lock arm 219 rotate about the pivot point 259 where the lock arm 219 rotates the lockout element 265 to the position shown in FIG. 17 to disable the knife lockout function. When the lever arm 215 is rotated about the pivot point 259 in the first direction, the lock arm 219 also rotates about the pivot point 259 in the same direction. The lock arm 219 then pushes on the lockout element 265 causing it to rotate in the opposite direction to unlock the knife lockout element 265, as shown in FIG. 17.

[0111] The above described knife lockout disabling mechanisms 8, 108, 208 provide several advantages over conventional electrosurgical devices with knife lockout mechanisms that cannot be disabled. For example, the lockout disabling mechanisms 8, 108, 208 according to the present disclosure can be configured to fit in a form factor of current electrosurgical instruments with only a change to one of the housing shrouds 6a, 6b, 106a, 106b, 206a, 206b. The lockout disabling mechanism 8, 108, 208 generally moves between two states (off or on). Thus, the button portion of the slider 13, 113 can be slidably translated and the rotator 213 can move rotatably between the two positions or states but not in any intermediate positions between the two states. In one embodiment, the button 39, 139, 239 can be retrofitted into some existing electrosurgical instruments and locks into place without requiring any additional or new components to lock it in position. The button 39, 139, 239 can be configured to employ a spring that is already provided for the energy button 22, 122, 222 as described herein. Also, either the slider or rotator is operatively coupled to the energy button such that when the knife lockout disabling mechanism is activated, it moves the energy button 22, 122, 222 inward to provide a visual and tactile clue that the knife lockout feature is turned off.

[0112] FIGS. 18-44 illustrate additional views of the surgical instrument 102 with the jaw members 116a, 116b, cutting member, and lockout mechanism in various modes of operation, according to one embodiment.

[0113] FIGS. 18-25 illustrate the surgical instrument 102 shown in FIGS. 1 and 2 with the jaw 110 fully open and the lockout defeat mechanism 108 enabled, e.g., in the “ON” position. FIG. 18 is a side elevational view of the surgical instrument 102 shown in FIGS. 1 and 2 with the left housing 106a shroud removed, shaft assembly 112 sheaths removed, the jaw 110 fully open and the lockout defeat mechanism 108 enabled, e.g., in the “ON” position, according to one embodiment. Thus, the button 139 portion of the slider 113 is slidably moved proximally to locate it in the B position.

[0114] FIG. 19 is a side elevational view of the surgical instrument 102 shown in FIG. 18 with the right housing shroud 106b removed, according to one embodiment. The trigger 109 is located in the maximum distal position and the trigger plate 124 is engaged with the toggle clamp 145 and yoke 132, which are located in the maximum proximal position to set the jaws 110 in the fully open position. The slider 113 is set to the maximum proximal “B” position where the ramp 149 has rotated the lever arm 115. The lever arm 115 rotates the unlock arm 119 clockwise and the lockout element 165 counterclockwise to enable the lockout defeat mechanism 108. The lockout element 165 also depresses the energy button 122 to indicate that the lockout defeat mechanism 108 enabled in the “ON” position. This view also shows the position of the firing plate 128 sector gear meshed with the first pinion 133 prior to firing the cutting element. FIG. 20 is a side elevational view of the surgical instrument shown in FIG. 19 with the firing plate 128 removed, according to one embodiment. This view illustrates the position of the trigger 109 relative to the trigger plate 124, the toggle clamp 145, and the yoke 132. This view also shows the first pinion 133 meshed with the second pinion 134 which located behind the firing plate 128. FIG. 21 is a side elevational view of the surgical instrument 102 shown in FIG. 20 with the lockout defeat mechanism slider 113 removed, according to one embodiment, to better illustrate the position of the toggle clamp 145 when the jaws 110 are fully open. FIG. 22 is a side elevational view of the surgical instrument 102 shown in FIG. 20 with the toggle clamp 145 and the yoke 132 removed, according to one embodiment. This view shows the position of the rack 136 and the lock arm 157 relative to the position of the slider 113. In addition, this view shows the second pinion 134 meshed with the rack 136 when the cutting element has not yet been fired. FIG. 23 is a partial perspective view of the surgical instrument 102 shown in FIG. 22, according to one embodiment, which more clearly shows the lock arm 157 located in the notch 158 formed on top of the rack 136. When the unlock arm 119 is in the indicated position, as the toggle clamp 145 and yoke move in the distal direction, the unlock arm 119 acts on the lock arm 157 to disengage the lock arm 157 from the notch 158 in the rack 136 to defeat the lockout mechanism. Therefore, the rack 136 is able to advance distally when the firing plate 128 is rotated by the trigger 109. FIG. 24 is a partial perspective view of the surgical instrument shown in FIG. 23 with the firing plate 128 replaced, according to one embodiment, to show the relative position of the firing plate 128, the first and second pinions 133, 134 and the rack 136 prior to firing the cutting element. FIG. 25 is a partial perspective view of the surgical instrument 102 shown in FIG. 24 with the lockout defeat mechanism slider 113, lever arm 115, and lock arm 157 removed, according to one embodiment, to show the notch 158 or slot formed on top of the rack 136. As previously discussed, the lock arm 157 engages the notch 158 to prevent the rack 136 from advancing distally to fire the cutting element in response to the squeezing the trigger 109.

[0115] FIGS. 26-28 illustrate the surgical instrument 102 shown in FIGS. 1 and 2 with the jaw 110 fully open and the lockout defeat mechanism 108 disabled, e.g., in the “OFF” position. FIG. 26 is a side elevational view of the surgical instrument 102 shown in FIGS. 1 and 2 with the left housing shroud 106a removed, shaft assembly 112 sheaths removed, the jaw 110 fully open and the lockout defeat mechanism 108 disabled, e.g., in the “OFF” position, according to one embodiment. Thus, the button 139 portion of the slider 113 is slidably moved distally to locate it in the A position. FIG. 27 is a side elevational view of the surgical instrument 102 shown in FIG. 26 with the right housing shroud 106b removed, according to one embodiment. The trigger 109 is located in the maximum distal position and the trigger plate 124 is engaged with the toggle clamp 145 and yoke 132, which are located in the maximum proximal position to set the jaws 110 in the fully open position. The slider 113 is set to the maximum distal “A” position. The lever arm 115 holds the unlock arm 119 and the lockout element 165 in a substantially vertical position to disable the lockout defeat mechanism 108 and enable the lockout mechanism. This view also shows the position of the firing plate 128 sector gear meshed with the first pinion 133 prior to firing the cutting element. FIG. 28 is a partial perspective view of the surgical instrument 102 shown in FIG. 27 with the toggle clamp 145 and yoke 132 removed, according to one embodiment. As shown, the unlock arm 119 is located in a substantially vertical position. Accordingly, as the toggle clamp 145 and the yoke 132 slide distally, the lock arm 157 will not contact the unlock arm 119 and the lock arm 157 remains engaged with the notch 158 in the rack 136. In this configuration, the lockout mechanism is enabled and to fire the rack 136, the energy button 122 must be depressed to rotate the lockout element 165 counterclockwise to rotate the unlock arm 119 clockwise and in response rotate the lock arm 157 counterclockwise to disengage it from the notch 158 in the rack 136.

[0116] FIGS. 29-32 illustrate the surgical instrument 102 shown in FIGS. 1 and 2 with the jaw 110 fully closed, knife fully fired, and the lockout defeat mechanism 108 enabled, e.g., in the “ON” position. FIG. 29 is a side elevational view of the surgical instrument 102 shown in FIGS. 1 and 2 with the left housing shroud 106a removed, shaft assembly 112 sheaths removed, the jaw 110 fully closed, knife fully fired, and the lockout defeat mechanism 108 enabled, e.g., in the “ON” position, according to one embodiment. FIG. 30 is a side elevational view of the surgical instrument 102 shown in FIG. 29 with the right housing shroud 106b removed, according to one embodiment. As shown, the trigger 109 is squeezed fully proximally in direction C to straighten the toggle clamp 145 and advance the yoke 132 distally in direction H to push on the closure actuator and close the jaws 110. Further, the firing plate 128 is shown fully rotated in the counterclockwise to fully fire the knife. As previously discussed, the slider 113 has been slidably moved proximally in direction I to position B to rotate the lever arm 115 and the unlock arm 119 clockwise to rotate the lockout element 165 counterclockwise in response. When the slider 113 is located in position B, the unlock arm 119 will unlock, e.g., disengage, the lock arm 157 from the notch 158 to enable the rack 136 to move proximally in direction I in response to the firing plate 128 rotating counterclockwise while engaged to the first pinion 133. The first pinion 133 rotates clockwise and which in turn rotates the second pinion 134 counterclockwise to drive the rack 136 distally in direction H to drive the firing bar 117 and the knife distally in direction H. FIG. 31 is a side elevational view of the surgical instrument 102 shown in FIG. 30 with the lockout defeat mechanism slider 113, lever arm 119, and firing plate 128 removed, according to one embodiment, to show the position of trigger plate 124, toggle clamp 145, and yoke 132 when the jaws 110 are in the fully closed position. FIG. 32 is a partial perspective view of the surgical instrument 102 shown in FIG. 30, according to one embodiment. In this view, the unlock arm 119 is shown engaged with the lock arm 157 to release the lock arm 157 from the notch 158 in the rack 136 to enable the rack 136 to slide distally in direction H and fire the knife.

[0117] FIGS. 33-35 illustrate the surgical instrument 102 shown in FIGS. 1 and 2 with the jaw 110 fully closed, knife fully fired, and the lockout defeat mechanism 108 disabled, e.g., in the “OFF” position. FIG. 33 is a side elevational view of the surgical instrument shown in FIGS. 1 and 2 with the left housing shroud removed, shaft assembly sheaths removed, the jaw fully closed and the lockout defeat mechanism disabled in the “OFF” position, according to one embodiment. FIG. 34 is a side elevational view of the surgical instrument 102 shown in FIG. 33 with the right housing shroud 106b removed, according to one embodiment. Thus, the button 139 portion of the slider 113 is slidably moved distally to locate it in the A position. To fully close the jaw 110, the trigger 109 is squeezed in direction C to rotate the trigger plate 124 fully counterclockwise to straighten the toggle clamp 145 and advanced the yoke 132. To fully fire the knife while the lockout defeat mechanism 108 disabled, e.g., in the “OFF” position (in other words, the lockout mechanism is enabled) the energy button 122 must be depressed to rotate the lockout element 165 counterclockwise and rotate the unlock arm 119 clockwise to kick the lock arm 157 out of the notch 158 in the rack 136 and unlock the lockout mechanism. Once the lockout mechanism in unlocked, the trigger 109 can be fully squeezed in direction C to rotate the firing plate 128 counterclockwise. This rotates the first pinion 133 clockwise, the second pinion 134 counterclockwise, and the rack 136 is driven distally to fire the firing bar 117 distally in direction H to fire the knife 174 and the I-beam member 216. FIG. 35 is a partial perspective view of the surgical instrument 102 shown in FIG. 34, according to one embodiment. This view shows the energy button 122 depressed to rotate the lockout element 165 counterclockwise, which in turn rotates the unlock arm 119 clockwise to unlock the unlock arm 119 unlocking the lock arm 157 and enabling the rack 136 to fire the firing bar 117 and the knife.

[0118] FIGS. 36-38 illustrate the surgical instrument 102 shown in FIGS. 1 and 2 with the jaw 110 fully closed or clamped and the lockout defeat mechanism 108 enabled, e.g., in the “ON” position. FIG. 36 is a side elevational view of the surgical instrument 102 shown in FIGS. 1 and 2 with the left housing 106a shroud removed, shaft assembly 112 sheaths removed, the jaw 110 clamped and the lockout defeat mechanism 108 enabled, e.g., in the “ON” position, according to one embodiment. FIG. 37 is a side elevational view of the surgical instrument 102 shown in FIG. 36 with the right housing shroud 106b removed, according to one embodiment. In this view, the jaw 110 has been fully clamped but the knife has not yet been fired. Thus, the trigger plate 124 is fully rotated counterclockwise to straighten the toggle clamp 145 and drive the yoke 132 distally in direction H. Since the knife 174 has not been fired, the trigger 109 has not been fully squeezed and the firing plate 128 has not been rotated to actuate the rack 136. FIG. 38 is a partial perspective view of the surgical instrument 102 shown in FIG. 37, according to one embodiment. With the lockout defeat mechanism 108 enabled, e.g., in the “ON” position, when the jaw 110 is clamped, the lock arm 157 is unlocked by the unlock arm 119 when the toggle clamp 145 and the yoke 132 are advanced distally in direction H. As shown, the lock arm 157 has been disengaged from the notch 158 in the rack 136 to enable the rack 136 to drive the firing bar 117 and the knife without the need to first depress the energy button 122.

[0119] FIGS. 39-41 illustrate the surgical instrument 102 shown in FIGS. 1 and 2 with the jaw 110 fully closed clamped position and the lockout defeat mechanism 108 disabled, e.g., in the “OFF” position. FIG. 39 is a side elevational view of the surgical instrument 102 shown in FIGS. 1 and 2 with the left housing shroud 106a removed, shaft assembly 112 sheaths removed, the jaw 110 clamped and the lockout defeat mechanism 108 disabled, e.g., in the “OFF” position, according to one embodiment. FIG. 40 is a side elevational view of the surgical instrument 102 shown in FIG. 39 with the right housing shroud 106b removed, according to one embodiment. In this view, the jaw 110 has been fully clamped but the knife has not yet been fired. Thus, the trigger plate 124 is fully rotated counterclockwise to straighten the toggle clamp 145 and drive the yoke 132 distally in direction H. Since the knife has not been fired, the trigger 109 has not been fully squeezed and the firing plate 128 has not been rotated to actuate the rack 136. FIG. 41 is a partial perspective view of the surgical instrument 102 shown in FIG. 40, according to one embodiment. With the lockout defeat mechanism 108 disabled, e.g., in the “OFF” position, when the jaw 110 is clamped, the lock arm 157 is located in the notch 158 formed in the rack 136 to prevent the rack 136 from advancing distally in direction H. As shown, the energy button 122 has not been depressed to unlock the lockout mechanism, thus when the toggle clamp 145 and the yoke 132 are advanced distally in direction H, the unlock arm 116 is positioned substantially vertically relative to the lock arm 157 and cannot disengage it from the notch 158. As shown, the lock arm 157 is still engaged in the notch 158 formed of the rack 136 to disable the rack 136 from driving the firing bar 117 and the knife without first depressing the energy button 122 to unlock the lockout mechanism.

[0120] FIGS. 42-44 illustrate the surgical instrument 102 shown in FIGS. 1 and 2 with the jaw 110 clamped and the energy button 122 thrown to unlock the lockout mechanism. FIG. 42 is a side elevational view of the surgical instrument 102 shown in FIGS. 1 and 2 with the left housing shroud 106a removed, shaft assembly 112 sheaths removed, the jaw 110 clamped and the energy button 122 thrown to unlock the lockout mechanism, according to one embodiment. FIG. 43 is a side elevational view of the surgical instrument 102 shown in FIG. 42 with the right housing shroud 106b removed, according to one embodiment. As shown, the trigger plate 128 has been rotated counterclockwise by the trigger 109. The firing plate 128, however, has not been actuated. The energy button 122 has been thrown or depressed to unlock the lockout mechanism. FIG. 44 is a partial perspective view of the surgical instrument 102 shown in FIG. 43, according to one embodiment. As shown, the lock arm 157 has been disengaged from the notch 158 formed in the rack 136 to enable the rack to advance distally in direction H when the trigger 109 is fully squeezed in direction C to actuate the firing plate 128.

[0121] FIG. 45 is an exploded view of the shaft assembly 112, end effector 110, yoke 132, and rack 136 portions of the surgical instrument shown in FIGS. 1 and 2, according to one embodiment. FIG. 46 is a perspective view of the shaft assembly 112, end effector 110, yoke 132, and rack 136 in the assembled state according to one embodiment showing the functional components. With reference now to FIGS. 45-46, the shaft assembly 112 comprises an outer tube 100 which contains or houses the various functional components of the shaft assembly 112. An electrically insulative nonconductive tube 176 is slidably received within the outer tube 100. A clamp tube 161 is attached to the nonconductive tube 176. The functional components of the shaft assembly 112 are slidably contained within the within the nonconductive tube 176 whereas the conductive elements 107a, 107b employed to supply electrical energy to the end effector 110 electrodes 135 are located outside the nonconductive tube 176. A closure actuator 129 is coupled to the distal end of the yoke 132. The closure actuator 129 comprises a proximal portion and a distal portion. The distal portion of the closure actuator 129 is sized to be received within a closure spring 114. The proximal portion of the closure actuator 129 is sized to compress the closure spring 114. The closure spring 114 is coupled to a closure bar 142 through a spring to bar interface element 127. The distal end 172 of the closure bar 142 is operatively coupled to the jaws 116a, 116b by a pin 180 and closure linkages 178a, 178b. The jaws 116a, 116b are pivotally coupled by a pin 182 and rotatable support structures 146a, 146b formed in the top jaw 116a. The closure actuator 129 is coupled to the distal end of the yoke 132, which is operatively coupled to the toggle clamp 145 (FIG. 10, for example). As previously described, the toggle clamp 145 is movably coupled to the trigger plate 124 (FIG. 10), for example. Rotation of the trigger plate 124 straightens the toggle clamp 145 to drive the yoke 132 distally. Distal movement of the yoke 132 causes distal movement of the closure actuator 129 to compresses the closure spring 114 and drive the closure bar 142. Distal movement of the closure actuator 142 pivotally moves the first jaw member 116a from an open position to a closed position with respect to the second jaw member 116b, for example.

[0122] A firing bar 117 comprises a proximal end 117a and a distal end 117b. The proximal end 117a of the firing bar 117 is coupled to the distal end 130 of the rack 136. The rack 136 is received within the yoke 132. The firing bar 117 is received within the closure actuator 129, the spring to bar interface element 127, and the jaw open spring 138. The distal end 117b of the firing bar 117 is fixedly coupled to a knife pusher block 140, which is fixedly coupled to a cutting element 174 (knife). The cutting element 174 comprises flexible bands 174a, 174b, 174c, which are fastened by the knife pusher block 140 at the proximal end and by pins 144a, 144b at the distal end to form knife or cutting element having an I-beam configuration. As previously described, the teeth 131 of the sector gear of the firing plate 128 engage and rotate the pinions 133, 134, which drive the rack 136 distally. The rack 136 drives the firing bar 117, which in turn drives the flexible I-beam cutting element 174 when the lock arm 157 is disengaged from a notch 158 formed in the rack 136.

[0123] FIG. 47 is a side view of an end effector 110 portion of the surgical instrument 102 shown in FIGS. 1 and 2 with the jaws open, according to one embodiment. The closure bar 142 is operatively coupled to the proximal end of the top jaw 116a via the closure linkages 178a, 178b (not shown) and first and second pins 180a, 180b. The lower pin 180a is slidably movable within a slot 212. As the closure bar 142 moves distally in the direction indicated by arrow AA, the pin 180a slides in the slot 212 to and forces the second pin 180b to move upwardly in the direction indicated by arrow BB to force the top jaw 116a to rotate to a closed position as indicated by arrow CC. The top jaw 116a pivots about a pivot point defined by the fastener pin 182. The bottom jaw 116b comprises the electrode 135, which is electrically coupled to an energy source (e.g., an RF electrosurgical energy source). The flexible I-beam band knife comprises a knife or cutting element 174. The cutting element 174 and the fastener pins 144a, 144b form an I-beam member 216 that forces the jaws 116a, 116b shut when the cutting element 174 is fired by the rack 136 and firing bar 117, as previously described. The I-beam member 216 advances distally on tracks 210a, 210b formed in the respective upper and lower jaws 116a, 116b to force the jaws 116a, 116b shut and compress the tissue located therebetween. A ramp 204 is defined at the proximal end of the top track 210a in the top jaw 116a. Accordingly, a predetermined force is required to advance the I-beam member 216 over the ramp 204 before the I-beam member 216 engages the top track 210a to close the jaws 116a, 16b as the I-beam member 206 is advanced distally by the flexible I-beam band 142. In the present view, the I-beam member 216 is located behind the ramp 204 as the linkages 178a, 178b (not shown) close the jaws 116a, 116b.

[0124] It is worthy to note that any reference to “one aspect,” “an aspect,” “one embodiment,” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with the aspect is included in at least one aspect. Thus, appearances of the phrases “in one aspect,” “in an aspect,” “in one embodiment,” or “in an embodiment” in various places throughout the specification are not necessarily all referring to the same aspect. Furthermore, the particular features, structures or characteristics may be combined in any suitable manner in one or more aspects.

[0125] Although various embodiments have been described herein, many modifications, variations, substitutions, changes, and equivalents to those embodiments may be implemented and will occur to those skilled in the art. Also, where materials are disclosed for certain components, other materials may be used. It is therefore to be understood that the foregoing description and the appended claims are intended to cover all such modifications and variations as falling within the scope of the disclosed embodiments. The following claims are intended to cover all such modification and variations.

[0126] Although various embodiments have been described herein, many modifications, variations, substitutions, changes, and equivalents to those embodiments may be implemented and will occur to those skilled in the art. Also, where materials are disclosed for certain components, other materials may be used. It is therefore to be understood that the foregoing description and the appended claims are intended to cover all such modifications and variations as falling within the scope of the disclosed embodiments. The following claims are intended to cover all such modification and variations.