Patent Publication Number: US-2015066026-A1

Title: Switch assemblies for multi-function, energy-based surgical instruments

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     The present application claims the benefit of and priority to U.S. Provisional Application Ser. No. 61/872,001, filed on Aug. 30, 2013, the entire contents of which are incorporated herein by reference. 
    
    
     BACKGROUND 
     1. Background of Related Art 
     The present disclosure relates to energy-based surgical instruments and, more particularly, to switch assemblies for energy-based surgical forceps configured for treating and/or cutting tissue. 
     2. Technical Field 
     A hemostat or forceps is a plier-like instrument which relies on mechanical action between its jaws to grasp, clamp, and constrict tissue. Energy-based forceps utilize both mechanical clamping action and energy, e.g., electrosurgical energy, ultrasonic energy, light energy, microwave energy, heat, etc., to affect hemostasis by heating tissue to coagulate and/or cauterize tissue. Certain surgical procedures require more than simply cauterizing tissue and rely on the unique combination of clamping pressure, precise energy control, and gap distance (i.e., distance between opposing jaw members when closed about tissue) to “seal” tissue. Typically, once tissue is sealed, the surgeon has to accurately sever the tissue along the newly formed tissue seal. Accordingly, many tissue-sealing instruments have been designed which incorporate a knife or blade member which effectively severs the tissue after forming a tissue seal. More recently, tissue-sealing instruments have been designed to allow for energy-based tissue division. 
     SUMMARY 
     As is traditional, use of the term “distal” herein refers to an end of the apparatus or component thereof that is farther from an operator, while use of the term “proximal” herein refers to the end of the apparatus or component thereof that is closer to the operator. Further, to the extent consistent, any of the aspects and features of the present disclosure may be utilized in conjunction with any or all of the other aspects and features of the present disclosure. 
     In accordance with aspects of the present disclosure, a surgical instrument is provided. The surgical instrument generally includes an end effector assembly, a first switch assembly, and a second switch assembly. The end effector assembly includes first and second jaw members. One or both of the jaw members is movable relative to the other to grasp tissue therebetween. One or both of the jaw members is adapted to connect to a source of energy for treating tissue grasped between the jaw members. One or both of the jaw members is adapted to connect to a source of energy for electrically cutting tissue grasped between the jaw members. The first switch assembly is operably coupled to the end effector assembly and is selectively activatable for supplying energy to the jaw member(s) for treating tissue grasped between the jaw members. The second switch assembly is operably coupled to the end effector assembly and is selectively activatable for supplying energy to the jaw member(s) for electrically cutting tissue grasped between the jaw members. The second switch assembly is configured such that the tactile feel and range of motion during actuation of the second switch assembly to effect electrical tissue cutting mimics the tactile feel and range of motion of activation of a mechanical actuator that advances a cutting blade between the jaw members to mechanically cut tissue. 
     In some aspects of the present disclosure, the first switch assembly includes a depressible button. 
     In some aspects of the present disclosure, the first switch assembly includes a flex circuit. 
     In some aspects of the present disclosure, the first switch assembly includes a dome switch. 
     In some aspects of the present disclosure, the first and second switch assemblies are coupled to a progressive switch. 
     In some aspects of the present disclosure, the second switch assembly includes a rotatable lever disposed on each side of the surgical instrument. Each of the levers is rotatable from a first position to a second position to activate the second switch assembly. Further, the rotatable lever may be biased towards the first position. 
     In some aspects of the present disclosure, first and second shaft members are operably coupled to the end effector assembly. More specifically, the first and second shaft members are movable relative to one another between a spaced-apart position and an approximated position for moving the jaw members relative to one another to grasp tissue therebetween. 
     In some aspects of the present disclosure, the first switch assembly is positioned such that movement of the first and second shaft members from the spaced-apart position to the approximated position activates the first switch assembly. 
     In accordance with aspects of the present disclosure, a surgical instrument is provided that generally includes an end effector assembly, first and second shaft members, and a two-mode switch assembly. The end effector assembly includes first and second jaw members. One or both of the jaw members is movable relative to the other to grasp tissue therebetween. One or both of the jaw members is adapted to connect to a source of energy for treating tissue grasped between the jaw members. One or both of the jaw members is adapted to connect to a source of energy for electrically cutting tissue grasped between the jaw members. The first and second shaft members are coupled to the end effector assembly and are movable relative to one another between a spaced-apart position and first and second approximated positions for moving the jaw members relative to one another between an open position and first and second grasping positions. The first shaft member includes a flange extending therefrom towards the second shaft member. The flange includes a first portion and a second portion. The two-mode switch assembly is coupled to the second shaft member. The switch assembly includes a first switch member selectively activatable for activating the switch assembly in a first mode for supplying energy to the jaw member(s) for treating tissue grasped between the jaw members. The switch assembly further includes a second switch member selectively activatable for activating the switch assembly in a second mode for supplying energy to the jaw member(s) for electrically cutting tissue grasped between the jaw members. Movement of the shaft members to the first approximated position urges the first portion of the flange into the first switch member to activate the first switch member while movement of the shaft members to the second approximated position urges the second portion of the flange into the second switch member to activate the second switch member. 
     In some aspects of the present disclosure, the two-mode switch assembly is disposed within a housing positioned about the second shaft member. 
     In some aspects of the present disclosure, the second portion of the flange defines a relatively wide base extending from the first shaft member and the first portion of the flange defines a relatively narrow extension extending from the base. 
     In some aspects of the present disclosure, the first switch member of the two-mode switch assembly is disposed within an aperture defined through the second switch member. 
     In some aspects of the present disclosure, a safety selector is provided. The safety selector is selectively movable between a first position, inhibiting activation of both the first and second switch members of the two-mode switch assembly, a second position inhibiting activation of the second switch member of the two-mode switch assembly but permitting activation of the first switch member of the two-mode switch assembly, and a third position permitting activation of both the first and second switch members of the two-mode switch assembly. 
     In some aspects of the present disclosure, the safety selector includes one or more gripping flanges The gripping flange(s) is configured to facilitate movement of the safety selector between the first, second, and third positions. 
     In some aspects of the present disclosure, the safety selector is slidable along the second shaft member and relative to the two-mode switch assembly between the first, second, and third positions. 
     In accordance with aspects of the present disclosure, a surgical instrument is provided generally including an end effector assembly, a first switch member, a second switch member, and an activation member. The end effector assembly includes first and second jaw members. One or both of the jaw members is movable relative to the other to grasp tissue therebetween. One or both of the jaw members is adapted to connect to a source of energy for treating tissue grasped between the jaw members. One or both of the jaw members is adapted to connect to a source of energy for electrically cutting tissue grasped between the jaw members. The first switch member is selectively activatable for supplying energy to the jaw member(s) for treating tissue grasped between the jaw members. The second switch member is selectively activatable for supplying energy to the jaw member(s) for electrically cutting tissue grasped between the jaw members. The activation member includes first and second activation components. The activation member is movable in a first direction for urging the first activation component into the first switch member for activating the first switch member and is movable in a second direction opposite the first direction for urging the second activation component into the second switch member for activating the second switch member. 
     In some aspects of the present disclosure, the activation member includes a rotating assembly having first and second flanges, the rotating assembly is rotatable in the first direction such that the first flange is urged into contact with the first switch member to activate the first switch member and rotatable in the second direction such that the second flange is urged into contact with the second switch member to activate the second switch member. 
     In some aspects of the present disclosure, the rotating assembly is biased towards a neutral position wherein both the first and second flanges are displaced from the first and second switch members, respectively. 
     In some aspects of the present disclosure, the activation member includes a lever disposed about a fulcrum. The lever includes a first end and a second end and is tiltable about the fulcrum. In particular, the lever is tiltable about the fulcrum in the first direction such that the first end is urged into contact with the first switch member to activate the first switch member and tiltable in the second direction such that the second end is urged into contact with the second switch member to activate the second switch member. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Various aspects and features of the present disclosure are described herein with reference to the drawings wherein: 
         FIG. 1  is a perspective view of a surgical forceps provided in accordance with the present disclosure; 
         FIG. 2  is an enlarged, perspective view of a distal end of the forceps of  FIG. 1 ; 
         FIG. 3  is a perspective view of the forceps of  FIG. 1  with parts separated; 
         FIG. 4A  is a longitudinal, cross-sectional view of one configuration of switch assemblies for use with a forceps similar to the forceps of  FIG. 1 ; 
         FIG. 4B  is an enlarged view of the area of detail indicated as “ 4 B” in  FIG. 4A ; 
         FIG. 4C  is a side, cross-sectional view of the first switch assembly of  FIG. 4B  with the outer portion of the first switch assembly removed; 
         FIG. 5A  is a perspective view of the first switch assembly of  FIG. 4A ; 
         FIG. 5B  is a perspective view of the first switch assembly of  FIG. 4A  with the outer portion of the first switch assembly removed; 
         FIG. 5C  is a top view of the first switch assembly of  FIG. 4A ; 
         FIG. 6A  is a longitudinal, cross-sectional view of another configuration of switch assemblies for use with a forceps similar to the forceps of  FIG. 1 ; 
         FIG. 6B  is an enlarged view of the area of detail indicated as “ 6 B” in  FIG. 6A ; 
         FIG. 6C  is a cross-sectional view of the second switch assembly of  FIG. 6A ; 
         FIG. 7A  is a longitudinal, cross-sectional view of another configuration of switch assemblies for use with a forceps similar to the forceps of  FIG. 1 ; 
         FIG. 7B  is an enlarged view of the area of detail indicated as “ 7 B” in  FIG. 7A ; 
         FIG. 8A  is a longitudinal, cross-sectional view of another configuration of switch assemblies for use with a forceps similar to the forceps of  FIG. 1 ; 
         FIG. 8B  is an enlarged view of the proximal end of the forceps of  FIG. 8A ; 
         FIG. 8C  is a top view of the switch assemblies of  FIG. 8A ; 
         FIG. 8D  is a top view of the switch assemblies of  FIG. 8A  with a safety mechanism disposed in a first condition; 
         FIG. 8E  is a top view of the switch assemblies of  FIG. 8A  with the safety mechanism disposed in a second condition; 
         FIG. 8F  is a top view of the switch assemblies of  FIG. 8A  with the safety mechanism disposed in a third condition; 
         FIG. 9A  is a side view of another configuration of switch assemblies for use with a forceps similar to the forceps of  FIG. 1 ; 
         FIG. 9B  is an enlarged, partial cross-sectional view of the first and second switch assemblies of  FIG. 9A ; 
         FIG. 10A  is a longitudinal, cross-sectional view of another configuration of switch assemblies for use with a forceps similar to the forceps of  FIG. 1 ; 
         FIG. 10B  is an enlarged view of the area of detail indicated as “ 10 B” in  FIG. 10A ; and 
         FIG. 10C  is a cross-sectional view of the switch assemblies of  FIG. 10B  with the outer portions of the switch assemblies removed. 
     
    
    
     DETAILED DESCRIPTION 
     Referring now to  FIGS. 1-3 , a forceps provided in accordance with the present disclosure is shown generally identified by reference numeral  10 . Forceps  10  is configured for grasping, electrically treating, and electrically (including electro-mechanically) dissecting tissue. As such, and as will be described in greater detail below, forceps  10  includes multiple switch assemblies  50 ,  60  configured to facilitate electrical activation of forceps  10  in various modes of operation, e.g., an electrical treatment mode and an electrical cutting mode. Various embodiments of switch assemblies are shown in  FIGS. 1-10C  and described herein, any or all of which may be used in conjunction with any or all of the other switch assemblies provided in accordance with the present disclosure, depending on a particular purpose. Although the various switch assemblies are shown and configured for use with forceps similar to forceps  10 , it is contemplated that the various switch assemblies, aspects, and features of the present disclosure are equally applicable for use with any suitable multi-function surgical instrument. Obviously, different connections and considerations apply to each particular instrument and the assemblies and/or components thereof; however, the aspects, features, and operating characteristics of the switch assemblies remain generally consistent regardless of the particular instrument, assemblies, and/or components provided. For the purposes herein, forceps  10  is generally described. 
     Continuing with reference to  FIGS. 1-3 , forceps  10 , shown configured for use in open and/or laparoscopic surgical procedures, generally includes a mechanical forceps  20  and a disposable portion that includes a housing  70  and an electrode assembly  21 , both of which are releasably engagable with mechanical forceps  20 . Mechanical forceps  20  includes first and second elongated shaft members  12 ,  14 . Elongated shaft member  12  includes proximal and distal end portions  13 ,  17 , respectively, and elongated shaft member  14  includes proximal and distal end portions  15 ,  19 , respectively. Disposed at proximal end portions  13 ,  15  of shaft members  12 ,  14  are handle members  16 ,  18 , respectively, that are configured to allow a user to effect movement of at least one of shaft members  12 ,  14  relative to the other. Distal end portions  17 ,  19  of mechanical forceps  20  cooperate to define an end effector assembly  24  having opposing jaw members  42 ,  44  that extend distally from respective shaft members  12 ,  14 . Jaw members  42 ,  44  are movable relative to each other in response to movement of shaft members  12 ,  14 . 
     Shaft members  12 ,  14  are coupled to one another towards distal end portions  17 ,  19 , respectively, thereof via a pivot  25  such that movement of shaft members  12 ,  14  relative to one another from a spaced-apart position to one or more approximated positions effects corresponding movement of jaw members relative to one another from an open configuration, wherein jaw members  42 ,  44  are disposed in spaced relation relative to one another, to one or more closed positions, wherein jaw members  42 ,  44  cooperate to grasp tissue therebetween. 
     Each shaft member  12 ,  14  further includes a ratchet portion  32 ,  34 , respectively. Each ratchet portion  32 ,  34  extends from the proximal end portion  13 ,  15  of its respective shaft member  12 ,  14  towards the other ratchet  32 ,  34  in a generally vertically aligned manner such that the inner facing surfaces of each ratchet  32 ,  34  abut one another when shaft members  12 ,  14  are approximated. Each ratchet  32 ,  34  includes a plurality of flanges  33 ,  35 , respectively, that project from the inner facing surface of each ratchet  32 ,  34  such that ratchets  32 ,  34  may interlock at one or more positions corresponding to one or more closed positions of jaw members  42 ,  44 . These one or more closed positions of jaw members  42 ,  44  each impart a specific closure pressure to tissue grasped between jaw members  42 ,  44  of end effector assembly  24 , thus allowing for effective treatment of a wide range of tissue types and sizes. 
     Referring still to  FIGS. 1-3 , housing  70  includes a pair of housing halves  70   a ,  70   b  configured to matingly engage and releasably encompass at least a portion of shaft member  14  therebetween. An interior of each housing half  70   a ,  70   b  may include a plurality of cooperating mechanical interfaces, e.g., protrusions and recesses, pins and apertures, or other suitable latching mechanisms, disposed at various positions to effect mechanical coupling of housing halves  70   a ,  70   b  to form housing  70  about shaft member  14 . 
     Disposable electrode assembly  21  extends distally from housing  70  and is bifurcated at the distal end thereof to define two portions  103  and  105 . First portion  103  is configured to releasably engage jaw member  42  and support a first electrode  110 , while second portion  105  is configured to releasably engage jaw member  44  and support a second electrode  120 , as will be described in greater detail below. A pair of wires  61 ,  62  are electrically connected to the electrodes  110 ,  120 , respectively, extend through housing  70 , couple to switch assemblies  50 ,  60 , and ultimately bundle to form a cable  28  that terminates at a terminal connector  30 . Terminal connector  30  is configured to releasably couple to a suitable energy source such as an electrosurgical generator (not shown) for providing energy to forceps  10 . 
     Electrode  110  includes an electrically conductive sealing surface  116  configured to conduct electrosurgical energy therethrough, while an electrically insulative substrate  111  of first portion  103  serves to electrically insulate jaw member  42  from sealing surface  116 . Sealing surface  116  and substrate  111  are attached to one another by any suitable method of assembly such as, for example, snap-fit engagement or by overmolding substrate  111  to sealing surface  116 . Substrate  111  includes a plurality of bifurcated anchor members  112  extending therefrom that are configured to compress during insertion into a corresponding plurality of sockets  41  disposed at least partially through an inner facing surface  45  of jaw member  42  and subsequently expand to releasably engage corresponding sockets  41  after insertion to couple first portion  103  to inner facing surface  45  of jaw member  42 . Substrate  111  also includes an alignment pin (not shown, similar to pin  124 ) that is configured to engage an aperture  67  disposed at least partially through inner facing surface  45  of jaw member  42  to ensure proper alignment of electrode  110  with jaw member  42  during assembly. Sealing surface  116  includes a proximal extension portion  117  configured to couple to a first prong member  118  of disposable electrode assembly  21  to thereby electrically connect sealing surface  116  to wire  61 . 
     With continued reference to  FIGS. 1-3 , and similarly as described above with respect to first portion  103 , second portion  105  includes an electrode  120  having an electrically conductive sealing surface  126  configured to conduct electrosurgical energy therethrough. Second portion  105  further includes an electrically insulative substrate  121  including a plurality of bifurcated anchor members  122  extending therefrom that are configured to compress during insertion into a corresponding plurality of sockets  43  disposed at least partially through an inner facing surface  47  of jaw member  44  and subsequently expand to releasably engage corresponding sockets  43  after insertion to couple second portion  105  to inner facing surface  47  of jaw member  44 . Substrate  121  also includes an alignment pin  124  that is configured to engage an aperture  69  disposed at least partially through inner facing surface  47  of jaw member  44  to ensure proper alignment of electrode  120  with jaw member  44  during assembly. Sealing surface  126  includes a proximal extension portion  127  configured to mechanically couple to a second prong (not shown, similar to first prong  118 ) of disposable electrode assembly  21  to thereby electrically connect sealing surface  126  to wire  62 . 
     One of the first and second portions  103 ,  105  of disposable electrode assembly  21 , e.g., first portion  103 , further includes an electrical cutting electrode  130  disposed within a longitudinal slot  132  extending along sealing surface  116 . A portion of substrate  111  disposed within slot  132  extends between electrical cutting electrode  130  and sealing surface  116  on either side of electrical cutting electrode  130  to electrically insulate electrical cutting electrode  130  from sealing surface  126 . Substrate  111  further extends between electrical cutting electrode  130  and jaw member  44  to electrically insulate electrical cutting electrode  130  from jaw member  42 . The other portion, e.g., second portion  105 , likewise includes a slot (not shown, similar to slot  132 ) defined within the sealing surface  126 . A portion of substrate  121  is disposed within the slot (not shown) to oppose cutting electrode  130 , thus maintaining electrical insulation between electrical cutting electrode  130  and both sealing surface  126  and jaw member  44  when jaw members  42 ,  44  are disposed in the one or more closed positions. 
     A third prong  138  of disposable electrode assembly  21  coupled to a third wire  63  is engaged to electrical cutting electrode  130  to electrically connect electrical cutting electrode  130  to third wire  63 . Third wire  63  extends through housing  70 , couples to first and second switch assemblies  50 ,  60 , and ultimately bundles with first and second wires  61 ,  62  to form cable  28 . 
     Continuing with reference to  FIGS. 1-3 , to selectively control the supply of energy to electrodes  110 ,  120 ,  130  for treating and/or dissecting tissue grasped between jaw members  42 ,  44 , housing  70  includes first and second switch assemblies  50 ,  60 , each including a pair of depressible activation buttons  50   a ,  50   b  and  60   a ,  60   b , respectively. First switch assembly  50  includes a depressible activation button  50   a ,  50   b  disposed on either side of housing  70 . Activation buttons  50   a ,  50   b  of first switch assembly  50  are electrically coupled between the energy source (not shown) and first and second electrodes  110 ,  120  via wires  61 ,  62 . As such, depression of either or both of activation buttons  50   a ,  50   b  energizes electrode  110  to a relative positive potential and electrode  120  to a relatively negative potential (although this configuration may be reversed) to establish a potential gradient between electrodes  110 ,  120  for conducting energy through tissue grasped between jaw members  42 ,  44  to treat, e.g., seal, tissue. Second switch assembly  60  includes a depressible activation button  60   a ,  60   b  disposed on either side of housing  70 . Activation buttons  60   a ,  60   b  of second switch assembly  60  are coupled between the energy source (not shown) and electrical cutting electrode  130  via wire  63  such that depression of either or both of activation buttons  60   a ,  60   b  energizes electrical cutting electrode  130  to a relatively positive potential and electrodes  110 ,  120  to a relatively negative potential. Accordingly, a potential gradient is established therebetween for conducting energy through tissue grasped between jaw members  42 ,  44  to cut tissue. 
     Turning now to  FIGS. 4A-10C , various embodiments of switch assemblies configured for use with forceps  10  (or forceps similar to forceps  10 ) for selectively controlling the supply of energy to electrodes  110 ,  120 ,  130  (or electrodes similar to electrodes  110 ,  120 ,  130 ) for treating and/or dissecting tissue grasped between jaw members  42 ,  44  (or jaw members similar to jaw members  42 ,  44 ) are described. For the purpose of brevity, and given the description of forceps  10  above, only the distinguishing aspects and features of the switch assemblies of  FIGS. 4A-10C  and the forceps used therewith will be described in detail below. 
     With reference to  FIGS. 4A-4C  and  5 A- 5 C, another forceps  10   a  similar to forceps  10  ( FIGS. 1-3 ) is shown including first and second switch assemblies  150 ,  160  disposed within housing  70   aa  and coupled between the source of energy (not shown) and end effector assembly  24   a  via wires  61   a ,  62   a ,  63   a . With particular reference to  FIGS. 5A-5C , first switch assembly  150  is configured for selectively energizing electrodes, e.g., electrodes similar to electrodes  110 ,  120  ( FIG. 3 ), for operation in a tissue treatment mode, e.g., for sealing tissue grasped between jaw members  42   a ,  44   a . First switch assembly  150  includes a frame  152 , a pair of depressible activation members  154  and a flex circuit assembly  156 . Frame  152  defines first and second spaced-apart walls  153   a ,  153   b , respectively, each of which is configured to operably receive one of the depressible activation members  154  on an outwardly-facing side thereof. A slot  153   c  defined between first and second walls  153   a ,  153   b  is configured to receive shaft member  14   a  of mechanical forceps  20   a  for releasably engaging first switch assembly  150  about mechanical forceps  20   a . Frame  152  may be fixedly engaged to one of the housing portions of housing  70   aa  or may be releasably engagable with one of the housing portions of housing  70   aa  upon engagement of housing  70   aa  about shaft member  14   a  of mechanical forceps  20   a . In either configuration, shaft member  14   a  is inserted through the open end of slot  153   c  of frame  152  until shaft member  14   a  is seated between walls  153   a ,  153   b  at the base of slot  153   c  of frame  152 . Openings in the housing portions of housing  70   aa  adjacent depressible activation members  154  provide user-access to depressible activation members  154  from either side of housing  70   aa  to permit selective activation of first switch assembly  150 . 
     Continuing with reference to  FIGS. 5A-5C , and as mentioned above, a depressible activation member  154  is operably engaged to each wall  153   a ,  153   b  of frame  152 . More specifically, depressible activation members  154  each include a finger-contact portion  155   a  having a connector  155   b  extending therefrom. Finger-contact portions  155   a  provide an expanded surface area configured to facilitate a user&#39;s ability to depress depressible activation members  154 . Connectors  155   b  extend from finger-contact portions  155   a  and define transverse pivot bars  155   c  at the free ends thereof. Transverse pivot bars  155   c  are received within hinge recesses  155   d  defined on the outwardly-facing surfaces of walls  153   a ,  153   b  of frame  152 . This hinged-engagement of connectors  155   b  of depressible activation members  154  to frame  152  allows finger-contact portions  155   a  of depressible activation members  154  to be selectively depressible from an initial position to a depressed position for selectively activating first switch assembly  150 , as will be described in greater detail below. Protrusions  155   e  ( FIG. 5C ) defined on the inwardly-facing surfaces of finger-contact portions  155   a  of depressible activation members  154  facilitate the activation of first switch assembly  150 . Further, connectors  155   b , pivot bars  155   c , and/or hinge recesses  155   d  may be configured such that finger-contact portions  155   a  are biased towards the initial position. Alternatively or additionally, a biasing member (not shown) may be provided for similar purposes. 
     Flex circuit assembly  156  of first switch assembly  150  includes a body  157  extending along the base of frame  152  and a pair of flanges  158  that extend along walls  153   a ,  153   b  of frame  152  adjacent finger-contact portions  155   a  of depressible activation members  154 . Flanges  158  each include a dome switch  159  disposed on an outwardly facing surface thereof. Dome switches  159  are electrically coupled to wires  61   a ,  62   a  via the internal circuitry of flex circuit assembly  156  so as to selectively permit the transmission of energy from the energy source (not shown) to the electrodes, e.g., electrodes  110 ,  120  ( FIG. 3 ). Dome switches  159  are normally biased towards an un-actuated state, disconnecting the electrical path through first switch assembly  150 . However, upon actuation of one or both of dome switches  159 , e.g., via depression of one or both depressible activation members  154  such that at least one of protrusions  155   e  urges at least one of dome switches  159  to an actuated position, the electrical path is reestablished, thus allowing energy transmission along wires  61   a ,  62   a  from the energy source (not shown), through first switch assembly  150 , to the electrodes, e.g., electrodes  110 ,  120  ( FIG. 3 ). More specifically, upon activation of one or both of dome switches  159 , electrode  110  ( FIG. 3 ) is energized to a relative positive potential and electrode  120  ( FIG. 3 ) to a relatively negative potential (although this configuration may be reversed) to establish a potential gradient between electrodes  110 ,  120  ( FIG. 3 ) for conducting energy through tissue grasped between jaw members  42   a ,  44   a  to treat, e.g., seal, tissue. 
     Referring again to  FIGS. 4A-4C , second switch assembly  160  is provided to selectively control the supply of energy to the electrodes, e.g., electrodes  110 ,  120 ,  130  ( FIG. 3 ), for operation of end effector assembly  24   a  in an electrical cutting mode, e.g., to electrically cut tissue grasped between jaw members  42   a ,  44   a . Second switch assembly  160  includes a pair of activation levers  162  disposed on either side of shaft member  14   a  and a pair contact switch members  164  disposed on either side of shaft member  14   a  (although only one of each is shown in  FIGS. 4A-4C ). Each activation lever  162  is pivotably coupled to one of the housing portions of housing  70   aa  via a pivot  163   a  at a first end thereof and extends from housing  70   aa , toward shaft member  12   a , to a free end thereof. A transverse, outwardly-protruding nub  163   b  is disposed at the free end of each lever  162  to facilitate grasping either lever  162  for rotating either lever  162  about its respective pivot  163   a . As will be described in greater below, levers  162  are pivotable about pivots  163   a  and relative to housing  70   aa  from a distal position to a proximal position to energize electrodes  110 ,  120 ,  130  ( FIG. 3 ) for conducting energy through tissue grasped between jaw members  42   a ,  44   a  to cut tissue. Further, a biasing member  163   c  may be provided to bias lever  162  towards the distal position. 
     Contact switch members  164  are electrically coupled to wires  61   a ,  62   a ,  63   a  via the internal circuitry of contact switch members  164  so as to selectively permit the transmission of energy from the energy source (not shown) to electrodes  110 ,  120 ,  130  ( FIG. 3 ). More specifically, contact switch members  164  each include a contact finger  165  that is normally biased, e.g., via a living hinge  166 , towards an un-actuated state, disconnecting the electrical path through second switch assembly  160 . However, upon urging of either of contact fingers  165  into contact with the respective body  167  of the contact switch member  164 , the electrical path is reestablished, thus allowing energy transmission along wires  61   a ,  62   a ,  63   a  from the energy source (not shown) through second switch assembly  160  to end effector assembly  24   a  to energize electrical cutting electrode  130  ( FIG. 3 ) to a relatively positive potential and electrodes  110 ,  120  ( FIG. 3 ) to a relatively negative potential for conducting energy through tissue grasped between jaw members  42   a ,  44   a  to cut tissue. Contact switch members  164  may be configured as on/off switches, e.g., wherein electrical contact between contact fingers  165  and body  167  supplies constant energy to end effector assembly  24   a , or, alternatively, may be configured as progressive switches, e.g., where the further contact fingers  165  are urged into contact with bodies  167 , the more energy is supplied to end effector assembly  24   a.    
     As mentioned above, levers  162  are pivotable about pivots  163   a  and relative to housing  70   aa  to activate contact switch members  164  to thereby energize electrodes  110 ,  120 ,  130  ( FIG. 3 ). By providing a lever  162  and corresponding contact switch member  164  on either side of forceps  10   a , activation of forceps  10   a  in the electrical cutting mode can be effected from either side of forceps  10 , e.g., via actuating either of levers  162 , depending on the surgeon&#39;s preference, anatomical considerations, or other factors. With levers  162  disposed in the distal position, proximally-facing surfaces  163   d  of levers  162  are spaced-apart from contact fingers  165  of contact switch members  164  such that contact fingers  165  remain biased towards the un-actuated state. Accordingly, in the distal position of levers  162 , the electrical path through second switch assembly  160  is disconnected. Upon pivoting of either of levers  162  from the distal position towards the proximal position, the proximally-facing surface  163   d  of the respective lever  162  contacts the corresponding contact finger  165  and urges the contact finger  165  into contact with the respective body  167  of the contact switch member  164  to reestablish the electrical path through second switch assembly  160  and thereby transmit energy from the energy source (not shown) to end effector assembly  24   a  for operation in the electrical cutting mode. 
     In embodiments where contact switch member  164  is configured as an on/off switch, the user may pivot lever  162  to the proximal position and maintain lever  162  in the proximal position sufficiently long so as to effect tissue cutting. The energy source (not shown), for example, may provide an audible alert indicating completion of tissue cutting, although other indicators are also contemplated. Alternatively, full pivoting of lever  162  from the distal position to the proximal position, which is slowed by the bias of biasing member  163   c  and living hinge  166 , provides sufficient “ON” time to electrically cut tissue grasped between jaw members  42   a ,  44   a . Thus, the surgeon is provided with a similar tactile feel and range of motion for electrically cutting tissue as compared to the more traditional approach of mechanically advancing a blade (not shown) between jaw members  42   a ,  44   a  to mechanically cut tissue grasped therebetween. In other words, activation of second switch assembly  160  mimics the activation of a mechanical blade (not shown). Further, by pivoting lever  162  through its full range of motion in this manner, energy-based tissue cutting can be achieved without the need for other indicators of cutting completion (although such indicators may also be provided). 
     In embodiments where contact switch member  164  is configured as a progressive switch, full pivoting of lever  162  from the distal position to the proximal position incrementally or continuously increases the energy applied to end effector assembly  24   a , e.g., in accordance with a pre-determined electrical cutting energy supply profile, such that, similarly as above, pivoting lever  162  through its full range of motion effects energy-based tissue cutting using the same tactile feel and range of motion as used in advancing a mechanical blade (not shown), e.g., mimicking mechanical tissue cutting. 
     Turning now to  FIGS. 6A-6C , another forceps  10   b  similar to forceps  10  ( FIGS. 1-3 ) is shown including first and second switch assemblies  250 ,  260  disposed within housing  70   bb  and coupled between the source of energy (not shown) and end effector assembly  24   b  via wires  61   b ,  62   b ,  63   b . Similarly as described above with respect to first switch assembly  150  ( FIGS. 5A-5C ), first switch assembly  250  is configured for selectively energizing electrodes, e.g., electrodes  110 ,  120  ( FIG. 3 ), for operation in a tissue treatment mode, e.g., for sealing tissue grasped between jaw members  42   b ,  44   b.    
     First switch assembly  250  includes an outer sleeve  252  and an inner activation button  254 . Outer sleeve  252  is fixedly disposed within housing  70   bb , while inner activation button  254  is slidably positioned within outer sleeve  252  and extends from outer sleeve  252  and housing  70   bb  towards shaft member  12   b . Inner activation button  254  is biased towards an un-activated position, wherein activation button  254  extends further towards shaft member  12   b . Shaft member  12   b  of mechanical forceps  20   b  includes an activation flange  256  extending towards shaft member  14   b  and, in particular, towards activation button  254  such that, upon sufficient approximation of shaft members  12   b ,  14   b , activation flange  256  contacts activation button  254  and urges activation button  254  inwardly into outer sleeve  252  to activate first switch assembly  250 . Upon activation of first switch assembly  250 , energy is transmitted along wires  61   b ,  62   b  from the energy source (not shown), through first switch assembly  250 , to the electrodes, e.g., electrodes  110 ,  120 , respectively ( FIG. 3 ). More specifically, upon activation of first switch assembly  250 , electrode  110  ( FIG. 3 ) is energized to a relative positive potential and electrode  120  ( FIG. 3 ) to a relatively negative potential (although this configuration may be reversed) to establish a potential gradient between electrodes  110 ,  120  ( FIG. 3 ) for conducting energy through tissue grasped between jaw members  42   b ,  44   b  to treat, e.g., seal, tissue. 
     Continuing with reference to  FIGS. 6A-6C , second switch assembly  260  is provided to selectively control the supply of energy to the electrodes, e.g., electrodes  110 ,  120 ,  130  ( FIG. 3 ), for operation of end effector assembly  24   b  in an electrical cutting mode, e.g., to electrically cut tissue grasped between jaw members  42   b ,  44   b . Second switch assembly  260  includes a pair of activation levers  262  disposed on either side of shaft member  14   b  and a pair activation buttons  268  disposed on either side of shaft member  14   b  proximally adjacent respective levers  262  (although only one of each is shown in  FIGS. 6A-6C ). 
     Each activation lever  262 , as best shown in  FIGS. 6B and 60 , is pivotably coupled to one of the housing portions of housing  70   bb  via a pivot  263  at a first end thereof and extends from housing  70   bb , toward shaft member  12   b , to a free end thereof. A transverse, outwardly-protruding nub  264  is disposed at the free end of each lever  262  to facilitate grasping either lever  262  for rotating either lever  262  about its respective pivot  263   a . Each activation lever  262  further includes a protrusion member  265  extending proximally therefrom. As will be described in greater detail below, protrusion members  265  are configured to contact activation buttons  268  to activate second switch assembly  260  upon rotation of one or both of activation levers  262  from a distal position to a proximal position. A biasing member  266  is also provided to bias lever  262  towards the distal position. 
     Activation buttons  268  of second switch assembly  260  are electrically coupled to wires  61   b ,  62   b ,  63   b  to selectively permit the transmission of energy from the energy source (not shown) to the electrodes, e.g., electrodes  110 ,  120 ,  130  ( FIG. 3 ). As best shown in  FIG. 6C , activation buttons  268  are normally biased towards an un-actuated state, disconnecting the electrical path through second switch assembly  260 . However, upon urging of either of protrusion members  265  of levers  262  into contact with the respective activation button  268 , the electrical path is reestablished, thus allowing energy transmission along wires  61   b ,  62   b ,  63   b  from the energy source (not shown) through second switch assembly  260  to end effector assembly  24   b  to energize electrical cutting electrode  130  to a relatively positive potential and electrodes  110 ,  120  ( FIG. 3 ) to a relatively negative potential for conducting energy through tissue grasped between jaw members  42   b ,  44   b  to cut tissue. 
     Similarly as described above with respect to second switch assembly  160  ( FIGS. 4A-5C ), second switch assembly  260  may be configured as an on/off switch or, alternatively, may be configured as a progressive switch. In either configuration, activation of second switch assembly  260  effects energy-based tissue cutting that mimics the tactile feel and range of motion used in actuating a mechanical actuator for mechanical tissue cutting. 
     Turning now to  FIGS. 7A-7B , another forceps  10   c  similar to forceps  10  ( FIGS. 1-3 ) is shown including first and second switch assemblies  350 ,  360  disposed within housing  70   c  and coupled between the source of energy (not shown) and end effector assembly  24   c  via wires  61   c ,  62   c ,  63   c . Similarly as described above with respect to the previous embodiments, first switch assembly  350  is configured for selectively energizing electrodes, e.g., electrodes  110 ,  120  ( FIG. 3 ), for operation in a tissue treatment mode, e.g., for sealing tissue grasped between jaw members  42   c ,  44   c.    
     First switch assembly  350  includes a rocker  352  operably positioned relative to a two-stage activation switch  358 . A pivot pin  353  pivotably retains rocker  352  within a recess defined within housing  70   c . Rocker  352  is pivotable about pivot pin  353  between an un-actuated position and an actuated position for activating forceps  10   c  for operation in a tissue treatment mode. More specifically, rocker  352  defines an exposed contact surface  352   a  that is positioned to oppose activation flange  355  of shaft member  12   c  and a protruding activation surface  352   b  that is configured to selectively contact and activate two-stage activation switch  358  in the first stage, or mode, e.g., the tissue treatment mode. 
     Activation flange  355  of shaft member  12   c  is offset relative to pivot pin  353  such that, upon sufficient approximation of shaft members  12   c ,  14   c , activation flange  355  contacts exposed contact surface  352   a  of rocker  352  and urges rocker  352  to rotate about pivot pin  353 , thereby rotating protruding activation surface  352   b  of rocker  352  into two-stage activation switch  358  to depress activation button  359  a first amount corresponding to the first stage, or mode of two-stage activation switch  358 . With two-stage activation switch  358  activated in this first stage, or mode, energy is transmitted along wires  61   c ,  62   c  from the energy source (not shown), through first switch assembly  350 , to the electrodes, e.g., electrodes  110 ,  120  ( FIG. 3 ), such that electrode  110  ( FIG. 3 ) is energized to a relative positive potential and electrode  120  ( FIG. 3 ) to a relatively negative potential (although this configuration may be reversed) to establish a potential gradient between electrodes  110 ,  120  ( FIG. 3 ) for conducting energy through tissue grasped between jaw members  42   c ,  44   c  to treat, e.g., seal, tissue, 
     Continuing with reference to  FIGS. 7A and 7B , second switch assembly  360  is provided to selectively control the supply of energy to the electrodes, e.g., electrodes  110 ,  120 ,  130  ( FIG. 3 ), for operation of end effector assembly  24   c  in an electrical cutting mode, e.g., to electrically cut tissue grasped between jaw members  42   c ,  44   c . Second switch assembly  360  includes a pair of activation levers  362  disposed on either side of shaft member  14   c , each of which are coupled to a linkage assembly  364  that is operably positioned relative to two-stage activation switch  358  such that, upon actuation of either activation lever  362 , two-stage activation switch  358  is activated in the second stage, or mode, wherein energy is supplied to end effector assembly  24   c  for electrically cutting tissue. 
     Each activation lever  362  is pivotably coupled to one of the housing portions of housing  70   c  via a pivot  363  at a first end thereof and extends from housing  70   c , toward shaft member  12   c , to a free end thereof. A transverse, outwardly-protruding nub  364  is disposed at the free end of each lever  362  to facilitate grasping and pivoting the lever  362  about pivot  363 . A biasing member  366  is also provided to bias lever  362  towards a distal position. 
     As mentioned above, each activation lever  362  is coupled to a linkage assembly  364 . More specifically, a first linkage bar  365   a  is pivotably coupled to and extends proximally from an intermediate portion of each activation lever  362 , e.g., between the first and free ends thereof, while a second linkage bar  365   b  is pivotably coupled to and extends proximally from each first linkage bar  365   a . Second linkage bars  365   b  each define a free end that is configured to selectively contact and depress activation button  359  of two-stage activation switch  358  a second amount corresponding to the second stage, or mode of two-stage activation switch  358  upon pivoting of the corresponding lever  362  about its pivot  363  from the distal position to a proximal position. Activation of activation button  359  of second switch assembly  360  in the second stage establishes and electrical path such that energy is transmitted along wires  61   c ,  62   c ,  63   c  from the energy source (not shown), through second switch assembly  360  to end effector assembly  24   c  to energize electrical cutting electrode  130  to a relatively positive potential and electrodes  110 ,  120  ( FIG. 3 ) to a relatively negative potential for conducting energy through tissue grasped between jaw members  42   c ,  44   c  to cut tissue. 
     Similarly as described above with respect to second switch assembly  160  ( FIGS. 4A-5C ), second switch assembly  360  may be configured as an on/off switch or, alternatively, may be configured as a progressive switch. In either configuration, activation of second switch assembly  360  effects energy-based tissue cutting that mimics the tactile feel and range of motion used in actuating a mechanical actuator for mechanical tissue cutting. 
     Turning now to  FIGS. 8A-8F , another forceps  10   d  similar to forceps  10  ( FIGS. 1-3 ) is shown including a two-mode switch assembly  450  and a safety selector  460 . Two-mode switch assembly  450  is coupled between the source of energy (not shown) and end effector assembly  24   d  via wires  61   d ,  62   d ,  63   d . As such, two-mode switch assembly  450  is configured for activation in a first mode for energizing electrodes, e.g., electrodes  110 ,  120  ( FIG. 3 ), for operation in a tissue treatment mode, e.g., for sealing tissue grasped between jaw members  42   d ,  44   d , and in a second mode for energizing electrodes, e.g., electrodes  110 ,  120 ,  130  ( FIG. 3 ), for operation in an electrical cutting mode, e.g., for cutting tissue grasped between jaw members  42   d ,  44   d . Safety selector  460  is selectively movable between a first position ( FIG. 8D ), wherein activation of two-mode switch assembly  450  in both the first and second modes is inhibited; a second position ( FIG. 8E ), wherein activation of two-mode switch assembly  450  in the first mode is permitted but activation in the second mode is inhibited; and a third position ( FIG. 8F ), wherein activation of two-mode switch assembly  450  in both the first and second modes is permitted. 
     Two-mode switch assembly  450  is seated within a recess defined within housing  70   d  and is accessible via a window  71   d  defined within housing  70   d , e.g., defined partly by each housing portion of housing  70   d . Two-mode switch assembly  450  includes a sleeve  452  fixedly engaged within housing  70   d  and inner and outer buttons  454 ,  456 , respectively, disposed within sleeve  452 . Inner and outer buttons  454 ,  456  are depressible relative to sleeve  452  to activate two-mode switch assembly  450  in the first and second modes, respectively. More specifically, outer button  456  defines an aperture  457  through which inner button  454  extends, thus permitting independent actuation of inner button  454 . 
     Shaft member  12   d  includes a tiered engagement flange  458  extending therefrom towards two-mode switch assembly  450 . More specifically, tiered engagement flange  458  includes a base portion  459   a  defining a relatively large width and an extension portion  459   b  defining a relatively narrower width, centered on base portion  459   a , and extending from base portion  459   a  towards two-mode switch assembly  450 . Upon sufficient approximation of shaft members  12   d ,  14   d , extension portion  459   b  is inserted into aperture  457  of outer button  456  to depress and activate inner button  454  without the need for activation of outer button  456 . Thus, activation of two-mode switch assembly  450  in only the first mode is possible. Base portion  459   a , on the other hand, is dimensioned larger than aperture  457  such that, upon further approximation of shaft members  12   d ,  14   d , base portion  459   a  contacts outer button  456  to depress and activate outer button  456 . In this situation, where both inner and outer buttons  454 ,  456  are depressed, two-mode switch assembly  450  is activated in the second mode. 
     By requiring further approximation of shaft members  12   d ,  14   d  to activate two-mode switch assembly  450  in the second mode, e.g., for electrically cutting tissue, as compared to the first mode, e.g., for tissue sealing, jaw members  42   d ,  44   d  are further approximated during tissue cutting as compared to tissue sealing. Such a feature is advantageous in that a larger clamping pressure on tissue is desirable in order to effect electrical tissue cutting as compared to tissue sealing. 
     As mentioned above, two-mode switch assembly  450  is configured for activation in a first mode or a second mode depending on the degree of approximation of shaft members  12   d ,  14   d . As also mentioned above, safety selector  460  is selectively movable between a first position ( FIG. 8D ), a second position ( FIG. 8E ), and a third position ( FIG. 8F ) for selectively inhibiting activation of two-mode switch assembly  450  in either or both of the first and second modes. Alternatively, safety selector  460  may be configured to include only two positions, e.g., the first and third positions or the second and third positions, depending on a particular purpose. The configuration and operation of safety selector  460  is described below. 
     Referring to  FIGS. 8D-8F , in conjunction with  FIGS. 8A-8C , safety selector  460  generally includes a control member  462  and a pair of grasping flanges  464 . Grasping flanges  464  are disposed on either side of housing  70   d  to facilitate operation of safety selector  460  from either side of forceps  10   d . Grasping flanges  464  extend through slots defined within housing  70   d  to engage control member  462  at the distal end of control member  462 . Control member  462  extends proximally through housing from the distal end thereof to the proximal end thereof. The proximal end of control member  462  includes first, second, and third segments  466 ,  467 ,  468 , respectively, that are configured for positioning within window  71   d  defined within housing  70   d  in the respective first, second, and third positions ( FIGS. 8D ,  8 E, and  8 F, respectively) of safety selector  460 , as will be described in greater detail below. Grasping flanges  464  are movable along housing  70   d  to translate control member  462  between the first, second, and third positions ( FIGS. 8D ,  8 E, and  8 F, respectively). A biasing member  469  biases control member  462  towards the first position. Further, any suitable releasable latching mechanism(s) or releasable engagement structure(s) (not shown) may be provided for releasably retaining control member  462  in the second and/or third position. 
     As shown in  FIG. 8D , in conjunction with  FIGS. 8A-8C , first segment  466  of control member  462  defines a solid, uninterrupted configuration, thereby inhibiting passage of both base portion  459   a  and extension portion  459   b  of flange  458  therethrough. As such, in the first position of control member  462 , activation of two-mode switch assembly  450  in either mode of operation is inhibited. 
     As shown in  FIG. 8E , in conjunction with  FIGS. 8A-8C , second segment  467  of control member  462  defines a relatively small sized aperture  467   a  configured to permit passage of extension portion  459   b  of flange  458  therethrough but to inhibit passage of base portion  459   a  of flange  458  therethrough. As such, in the second position of control member  462 , activation of two-mode switch assembly  450  in only the first mode of operation is permitted. 
     As shown in  FIG. 8F , in conjunction with  FIGS. 8A-8C , third segment  468  of control member  462  defines a relatively large sized aperture  468   a  configured to permit passage of both extension portion  459   b  of flange  458  and base portion  459   a  of flange  458  therethrough. As such, in the third position of control member  462 , activation of two-mode switch assembly  450  in either mode of operation is permitted. 
     Turning now to  FIGS. 9A and 9B , another forceps  10   e  similar to forceps  10  ( FIGS. 1-3 ) is shown including a two-mode rotating switch assembly  550  disposed on either side of forceps  10   e  (although only one side is shown and referred to herein for purposes of simplicity). Two-mode rotating switch assembly  550  is configured for activation in a first mode for energizing electrodes, e.g., electrodes  110 ,  120  ( FIG. 3 ), for operation in a tissue treatment mode, e.g., for sealing tissue grasped between jaw members  42   e ,  44   e , and in a second mode for energizing electrodes, e.g., electrodes  110 ,  120 ,  130  ( FIG. 3 ), for operation in an electrical cutting mode, e.g., for cutting tissue grasped between jaw members  42   e ,  44   e . Two-mode rotating switch assembly  550  is coupled between the source of energy (not shown) and end effector assembly  24   e  similarly as described above with respect to previous embodiments. 
     Two-mode rotating switch assembly  550  is mounted on housing  70   e  of forceps  10   e  and includes inner and outer rotating members  552 ,  554 , respectively, and first and second activation buttons  562 ,  564 , respectively. Inner and outer rotating members  552 ,  554  are engaged with one another such that rotation of outer rotating member  554  effects corresponding rotation of inner rotating member  552 . Inner rotating member  552  is disposed within housing  70   e  of and includes first, second, and third flanges  553   a ,  553   b ,  553   c , respectively, extending radially outwardly from inner rotating member  552 . First and second flanges  553   a ,  553   b  generally oppose one another, the use of which will be described in greater detail below. Third flange  553   c  is coupled to a pair of opposing biasing members  555   a ,  555   b  configured to bias two-mode rotating switch assembly  550  toward a neutral position. 
     Outer rotating member  554  includes a pair of generally opposed grasping arms  556   a ,  556   b , each including an outwardly-protruding nub  557   a ,  557   b , respectively, disposed at the free end thereof to facilitate grasping and rotating arms  556   a ,  556   b . As will be described in greater detail below, sufficient rotation of arms  556   a ,  556   b  from the neutral position in a first direction, e.g., a clockwise direction as viewed in  FIGS. 9A and 9B , activates two-mode rotating switch assembly  550  for operation in the first mode, while sufficient rotation of arms  556   a ,  556   b  from the neutral position in a second, opposite direction, e.g., a counterclockwise direction as viewed in  FIGS. 9A and 9B , activates two-mode rotating switch assembly  550  for operation in the second mode. 
     First and second activation buttons  562 ,  564  of two-mode rotating switch assembly  550  are mounted within housing  70   e  and are positioned on either side of inner rotating member  552 . More specifically, first activation button  562  is oriented to face and is positioned within the rotation path of first flange  553   a  of inner rotating member  552 , while second activation button  564  is oriented to face and is positioned within the rotation path of second flange  553   b  of inner rotating member  552 . First activation button  562  is coupled between the source of energy and the electrodes, e.g., electrodes  110 ,  120  ( FIG. 3 ), such that, upon activation of first activation button  562 , electrode  110  ( FIG. 3 ) is energized to a relative positive potential and electrode  120  ( FIG. 3 ) to a relatively negative potential (although this configuration may be reversed) to establish a potential gradient between electrodes  110 ,  120  ( FIG. 3 ) for conducting energy through tissue grasped between jaw members  42   e ,  44   e  to treat, e.g., seal, tissue. As such, grasping and rotating either or both arms  556   a ,  556   b  in the first direction rotates first flange  553   a  into contact with first activation button  562  to activate first activation button  562  for tissue treatment, e.g., tissue sealing. 
     Second activation button  564  is coupled between the source of energy and the electrodes, e.g., electrodes  110 ,  120 ,  130  ( FIG. 3 ), such that, upon activation of second activation button  564 , electrical cutting electrode  130  is energized to a relatively positive potential and electrodes  110 ,  120  ( FIG. 3 ) to a relatively negative potential for conducting energy through tissue grasped between jaw members  42   e ,  44   e  to cut tissue. As such, grasping and rotating either or both of arms  556   a ,  556   b  in the second direction rotates second flange  553   b  into contact with second activation button  564  to activate second activation button  562  for tissue cutting. 
     Turning now to  FIGS. 10A-10C , another forceps  10   f  similar to forceps  10  ( FIGS. 1-3 ) is shown including an activation first and second switch assemblies  650 ,  660  disposed within housing  70   f  and coupled between the source of energy (not shown) and end effector assembly  24   f  for selectively energizing electrodes  110 ,  120  ( FIG. 3 ) for operation in a tissue treatment mode, e.g., for sealing tissue grasped between jaw members  42   f ,  44   f , and for operation in a tissue cutting mode, e.g., for electrically cutting tissue grasped between jaw members  42   f ,  44   f , respectively. 
     First and second switch assemblies  650 ,  660  are mounted on a frame,  652 , similar to frame  152  ( FIGS. 5A-5C ) and each includes a flex circuit assembly  654 ,  664 , respectively, similar to flex circuit assembly  156  ( FIGS. 5A-5C ), having a dome switch  655   a ,  665   b  disposed on each of the flanges  655   b ,  665   b  thereof. For purposes of brevity, only the differences between first and second switch assemblies  650 ,  660  and first switch assembly  150  ( FIGS. 5A-5C ) will be described in detail below. 
     First and second switch assemblies  650 ,  660  are selectively and alternatively activated via depressing lever member  670  in the vicinity of the desired switch assembly  650 ,  660  to be activated. More specifically, lever member  670  is mounted about a fulcrum  676  and defines a first end  672  disposed adjacent first switch assembly  650  and a second end  674  disposed adjacent second switch assembly  660 . Lever member  670  is selectively and alternatively tiltable about fulcrum  676  towards first switch assembly  650 , e.g., such that first end  672  of lever member  670  contact and urges dome switch  655   a  into an activated position, and towards second switch assembly  660 , e.g., such that second end  674  of lever member  670  urges dome switch  665   a  into an activated position. Thus, upon sufficient tilting of lever member  670  to activate first switch assembly  650 , tissue treatment, e.g., sealing, can be effected while, on the other hand, upon sufficient tilting of lever member  670  to activate second switch assembly  660 , electrical tissue cutting can be effected. 
     While several embodiments of the disclosure have been shown in the drawings and described herein, it is not intended that the disclosure be limited thereto, as it is intended that the disclosure be as broad in scope as the art will allow and that the specification be read likewise. Therefore, the above description should not be construed as limiting, but merely as examples of particular embodiments. Those skilled in the art will envision other modifications within the scope and spirit of the claims appended hereto.