ELECTRICALLY-INSULATIVE HINGE FOR ELECTROSURGICAL JAW ASSEMBLY, BIPOLAR FORCEPS INCLUDING SAME, AND METHODS OF JAW-ASSEMBLY ALIGNMENT USING FASTENED ELECTRICALLY-INSULATIVE HINGE

[0001] 1. Technical Field

[0002] The present disclosure relates to joints and hinges used to connect movable components of an electrosurgical instrument and, more particularly, to an electrically-insulative hinge for use in an electrosurgical jaw assembly, a bipolar forceps including an electrically-insulative hinge, and methods of jaw-assembly alignment using a fastened electrically-insulative hinge.

[0003] 2. Discussion of Related Art

[0004] Electrosurgical instruments, such as electrosurgical forceps, have become widely used by surgeons. Electrosurgery involves application of high-frequency electrical current to a surgical site to cut, ablate, coagulate, cauterize or seal tissue.

[0005] The basic purpose of both monopolar and bipolar electrosurgery is to produce heat to achieve the desired tissue/clinical effect. In monopolar electrosurgery, devices use an instrument with a single, active electrode to deliver energy from an electrosurgical generator to tissue, and a patient return electrode or pad that is attached externally to the patient (e.g., a plate positioned on the patient's thigh or back) as the means to complete the electrical circuit between the electrosurgical generator and the patient. When the electrosurgical energy is applied, the energy travels from the active electrode, to the surgical site, through the patient and to the return electrode.

[0006] In bipolar electrosurgery, the electrosurgical device includes two electrodes that are located in proximity to one another for the application of current between their surfaces. Bipolar electrosurgical current travels from one electrode, through the intervening tissue to the other electrode to complete the electrical circuit. Bipolar instruments generally include end effectors, such as grippers, cutters, forceps, dissectors and the like.

[0007] Bipolar electrosurgical forceps utilize two generally opposing electrodes that are operably associated with the inner opposing surfaces of end effectors and that are both electrically coupled to an electrosurgical generator. Each electrode is charged to a different electric potential. By utilizing an electrosurgical forceps, a surgeon can utilize both clamping action and electrosurgical energy to cauterize, coagulate/desiccate and/or cut tissue and/or simply reduce or slow bleeding by controlling the intensity, frequency and duration of the electrosurgical energy applied to the tissue.

[0008] Typically, joints and hinges for use in electrosurgical instruments to connect movable components are formed from an electrically-insulative material to prevent electrical shorting between component parts and/or prevent the formation of alternate current paths through the instrument. As such, instrument designers have manufactured electrosurgical instruments that involve complex, rotating hinge configurations to isolate, insulate and/or control the electrosurgical active areas of the instrument.

[0009] Traditional metal hinge configurations generally include multiple, independent sub-assemblies. Typically, the sub-assemblies are overmolded with plastic material having high bond strength. These separately overmolded sub-assemblies are mechanically integrated and arranged in a series of manufacturing steps that often require tightly controlled, time-consuming processes to achieve proper jaw alignment. Additional steps are often undertaken to control other parameters associated with the rotational movement about the hinge, e.g., friction, torque, etc.

[0010] A continuing need exists for a simple and effective electrically-insulative hinge that can be readily integrated into the manufacturing process to electrically isolate the movable components of an electrosurgical instrument. Further need exists for the development of a manufacturing process that effectively fabricates an electrosurgical instrument including an electrically-insulative hinge that electrically isolates and structurally integrates the electrically-active components of the instrument and results in the formation of a reliable instrument that meets specific tolerance requirements for proper jaw alignment and/or gap distances.

[0011] The present disclosure relates to an end effector assembly suitable for use with a forceps. The end effector assembly includes opposing first and second jaw members pivotably mounted with respect to one another. The first jaw member includes one or more pivot holes defined therein configured to receive a portion of a pivot pin therein. The end effector assembly also includes an electrically-insulative hinge configured to electrically isolate the first and second jaw members from one another including one or more pivot-hole locators defined therein. The electrically-insulative hinge is attached to the second jaw member such that the one or more pivot-hole locators aligns with the one or more pivot holes defined in the first jaw member.

[0012] The present disclosure also relates to a bipolar forceps including a housing, a shaft extending from the housing and including a distal end configured to support an end effector assembly. The end effector assembly includes opposing jaw members pivotably mounted with respect to one another, each of the jaw members including a sealing surface associated therewith. The jaw members are moveable from a first position in spaced relation relative to one another to one or more subsequent positions wherein the sealing surfaces cooperate to grasp tissue therebetween. The end effector assembly also includes an electrically-insulative hinge configured to electrically isolate the jaw members from one another including one or more pivot-hole locators each having an aperture defined therein. The electrically-insulative hinge is attached to one of the jaw members such that the aperture of each of the one or more pivot-hole locators aligns with a pivot hole defined in the opposing jaw member, wherein the electrically-insulative hinge is configured to electrically isolate the jaw members from one another.

[0013] The present disclosure also relates to a method of manufacturing an end effector assembly including the initial steps of providing a first jaw member and providing a second jaw member including one or more pivot holes defined therethrough. The method also includes the steps of providing an electrically-insulative hinge including one or more pivot-hole locators defined therein, attaching the electrically-insulative hinge to the first jaw member such that the one or more pivot-hole locators align with the one or more pivot holes of the second jaw member, and pinning the first and second jaw members via the one or more pivot-hole locators and the one or more pivot holes such that the first and second jaw members are pivotably mounted with respect to one another.

[0014] The present disclosure also relates to a method of manufacturing an end effector assembly including the initial steps of providing a first jaw member including a first pivot hole defined therethrough and providing a second jaw member including a second pivot hole defined therethrough. The method also includes the steps of providing an electrically-insulative hinge including at least one pivot-hole locator defined therein, attaching the electrically-insulative hinge to the first jaw member such that the at least one pivot-hole locator aligns with the first pivot hole, providing a fixture configured to releaseably hold the first jaw member in contact with the second jaw member, providing a pivot pin, coupling the fixture to the first and second jaw members, and inserting the pivot pin through the at least one pivot-hole locator into the first and second pivot holes such that the first and second jaw members are pivotably mounted with respect to one another.

[0035] Hereinafter, embodiments of an electrically-insulative hinge for use in an electrosurgical jaw assembly, a bipolar forceps including an electrically-insulative hinge, and methods of jaw-assembly alignment using a fastened electrically-insulative hinge of the present disclosure are described with reference to the accompanying drawings. Like reference numerals may refer to similar or identical elements throughout the description of the figures. As shown in the drawings and as used in this description, and as is traditional when referring to relative positioning on an object, the term “proximal” refers to that portion of the apparatus, or component thereof, closer to the user and the term “distal” refers to that portion of the apparatus, or component thereof, farther from the user.

[0036] This description may use the phrases “in an embodiment,” “in embodiments,” “in some embodiments,” or “in other embodiments,” which may each refer to one or more of the same or different embodiments in accordance with the present disclosure. For the purposes of this description, a phrase in the form “A/B” means A or B. For the purposes of the description, a phrase in the form “A and/or B” means “(A), (B), or (A and B)”. For the purposes of this description, a phrase in the form “at least one of A, B, or C” means “(A), (B), (C), (A and B), (A and C), (B and C), or (A, B and C)”.

[0037] Electromagnetic energy is generally classified by increasing energy or decreasing wavelength into radio waves, microwaves, infrared, visible light, ultraviolet, X-rays and gamma-rays. As it is used in this description, “microwave” generally refers to electromagnetic waves in the frequency range of 300 megahertz (MHz) (3×10⁸ cycles/second) to 300 gigahertz (GHz) (3×10¹¹ cycles/second). As it is used in this description, “ablation procedure” generally refers to any ablation procedure, such as, for example, microwave ablation, radiofrequency (RF) ablation, or microwave or RF ablation-assisted resection. As it is used in this description, “transmission line” generally refers to any transmission medium that can be used for the propagation of signals from one point to another.

[0038] Various embodiments of the present disclosure provide a bipolar forceps with an end effector assembly including opposing jaw members pivotably mounted with respect to one another, and an electrically-insulative hinge fastened to one of the jaw members, wherein the electrically-insulative hinge is configured to electrically isolate the jaw members from one another. Various embodiments of the present disclosure provide methods of manufacturing an end effector assembly including the presently-disclosed electrically-insulative hinge.

[0039] Embodiments of the presently-disclosed bipolar forceps may be suitable for utilization in endoscopic surgical procedures, such as shown in FIG. 16, and/or suitable for utilization in open surgical applications. Embodiments of the presently-disclosed bipolar forceps may be implemented using electromagnetic radiation at microwave frequencies, RF frequencies or at other frequencies. An electrosurgical system including the presently-disclosed endoscopic bipolar forceps operatively coupled to an electrosurgical energy source (e.g., 16 shown in FIG. 1) according to various embodiments is designed and configured to operate at frequencies between about 300 KHz and about 10 GHz.

[0040] Although the following description describes the use of an endoscopic bipolar forceps, the teachings of the present disclosure may also apply to a variety of electrosurgical devices that include hinges used to connect movable components thereof.

[0041] In FIG. 1, an embodiment of an endoscopic bipolar forceps 10 is shown for use with various surgical procedures and generally includes a housing 20, a handle assembly 30, a rotatable assembly 80, a trigger assembly 70 and an end effector assembly 100 that mutually cooperate to grasp, seal and/or divide tubular vessels and vascular tissue (e.g., 1420 shown in FIGS. 14 through 16). Although FIG. 1 depicts a bipolar forceps 10 for use in connection with endoscopic surgical procedures, the teachings of the present disclosure may also apply to more traditional open surgical procedures. For the purposes herein, the forceps 10 is described in terms of an endoscopic instrument; however, it is contemplated that an open version of the forceps may also include the same or similar operating components and features as described below.

[0042] Forceps 10 includes a shaft 12 that has a distal end 16 configured to mechanically engage the end effector assembly 100 and a proximal end 14 configured to mechanically engage the housing 20. In some embodiments, the shaft 12 has a length from a proximal side of the handle assembly 30 to a distal side of the forceps 10 in a range of about 7 centimeters to about 44 centimeters.

[0043] Details of how the shaft 12 connects to the end effector assembly 100 are described in more detail below with respect to FIG. 2. The proximal end 14 of the shaft 12 is received within the housing 20, and connections relating thereto are disclosed in commonly assigned U.S. Pat. No. 7,150,097 entitled “METHOD OF MANUFACTURING JAW ASSEMBLY FOR VESSEL SEALER AND DIVIDER”, commonly assigned U.S. Pat. No. 7,156,846 entitled “VESSEL SEALER AND DIVIDER FOR USE WITH SMALL TROCARS AND CANNULAS”, commonly assigned U.S. Pat. No. 7,597,693 entitled “VESSEL SEALER AND DIVIDER FOR USE WITH SMALL TROCARS AND CANNULAS” and commonly assigned U.S. Pat. No. 7,771,425 entitled “VESSEL SEALER AND DIVIDER HAVING A VARIABLE JAW CLAMPING MECHANISM”.

[0044] Forceps 10 includes an electrosurgical cable 310. Electrosurgical cable 310 may be formed from a suitable flexible, semi-rigid or rigid cable, and may connect directly to an electrosurgical power generating source 16, e.g., a microwave or RF electrosurgical generator. In some embodiments, the electrosurgical cable 310 connects the forceps 10 to a connector 17, which further operably connects the instrument 10 to the electrosurgical power generating source 16. Electrosurgical cable 310 may be internally divided into one or more cable leads (e.g., 311 shown in FIG. 12) each of which transmits electrosurgical energy through their respective feed paths to the end effector assembly 100.

[0045] Electrosurgical power generating source 16 may be any generator suitable for use with electrosurgical devices, and may be configured to provide various frequencies of electromagnetic energy. Examples of electrosurgical generators that may be suitable for use as a source of electrosurgical energy are commercially available under the trademarks FORCE EZ™, FORCE FX™, SURGISTAT™ II, and FORCE TRIAD™ offered by Covidien. Electrosurgical cable 310 may additionally, or alternatively, provide a conduit (not shown) configured to provide coolant fluid from a coolant source (not shown) to one or more components of the forceps 10. Forceps 10 may alternatively be configured as a wireless device or battery-powered.

[0046] End effector assembly 100 may be selectively and releaseably engageable with the distal end 16 of the shaft 12, and/or the proximal end 14 of the shaft 12 may be selectively and releaseably engageable with the housing 20 and the handle assembly 30. In either of these two instances, the forceps 10 would be considered “partially disposable” or “reposable”, e.g., a new or different end effector assembly 100 (or end effector assembly 100 and shaft 12) selectively replaces the old end effector assembly 100 as needed. As can be appreciated, some of the presently-disclosed electrical and/or mechanical connections may have to be altered to modify the instrument to a reposable forceps.

[0047] End effector assembly 100 generally includes a pair of opposing jaw members 110 and 120 pivotably mounted with respect to one another. End effector assembly 100 includes an electrically-insulative hinge 450 (shown in FIGS. 12 and 13), which is described in more detail later in this disclosure, configured to electrically isolate the jaw members from one another. Electrically-insulative hinge 450 can be used to align the jaw members 110 and 120 during assembly of the end effector assembly 100, such as shown FIG. 7. End effector assembly 100 is designed as a unilateral assembly, i.e., the end effector assembly 100 includes a stationary or fixed jaw member 120 mounted in fixed relation to the shaft 12 and a pivoting jaw member 110 mounted about a pivot pin 103 (shown in FIGS. 10 through 13) coupled to the stationary jaw member 120. Alternatively, the forceps 10 may include a bilateral jaw assembly, i.e., both jaw members move relative to one another. A reciprocating sleeve 60 (shown in FIGS. 11 through 14) is slidingly disposed within the shaft 12. Pulling the sleeve 60 proximally closes the jaw members 110 and 120 about tissue grasped therebetween, and pushing the sleeve 60 distally opens the jaw members 110 and 120. Sleeve 60 is remotely operable by a drive assembly (not shown).

[0048] As shown in FIGS. 10 through 13, the pivoting jaw member 110 includes a detent or protrusion 117 that extends from the pivoting jaw member 110 through an aperture 62 disposed within the reciprocating sleeve 60. As best shown in FIG. 11, the protrusion 117 is configured to matingly engage the aperture 62 of sleeve 60 upon retraction thereof. Pivoting jaw member 110 is actuated by sliding the reciprocating sleeve 60 axially within the shaft 12 such that a distal end of the aperture 62 abuts against the detent 117 on the pivoting jaw member 110. For example, proximal movement of the sleeve 60 engages detent 117 to pivot the jaw member 110 to a closed position for grasping purposes.

[0049] As shown in FIG. 1, the end effector assembly 100 is rotatable about a longitudinal axis “A-A” through rotation, either manually or otherwise, of the rotatable assembly 80. Rotatable assembly 80 generally includes two halves (not shown), which, when assembled about tube 160, form a generally circular rotatable member 82. Rotatable assembly 80, or portions thereof, may be configured to house a drive assembly (not shown) and/or a knife assembly 180 (shown in FIG. 13), or components thereof. Examples of rotatable assembly embodiments, drive assembly embodiments, and knife assembly embodiments of the forceps 10 are described in the above-mentioned, commonly-assigned U.S. Pat. Nos. 7,150,097, 7,156,846, 7,597,693 and 7,771,425.

[0050] Handle assembly 30 includes a fixed handle 50 and a movable handle 40. In some embodiments, the fixed handle 50 is integrally associated with the housing 20, and the handle 40 is selectively movable relative to the fixed handle 50. Movable handle 40 of the handle assembly 30 is ultimately connected to the drive assembly (not shown) and mechanically cooperate to impart movement of the jaw members 110 and 120 from an open position, wherein the jaw members 110 and 120 are disposed in spaced relation relative to one another, to a clamping or closed position, wherein the jaw members 110 and 120 cooperate to grasp tissue (e.g., 1420 shown in FIG. 14) therebetween. Examples of handle assembly embodiments of the forceps 10 are described in the above-mentioned, commonly-assigned U.S. Pat. Nos. 7,150,097, 7,156,846, 7,597,693 and 7,771,425.

[0051] Forceps 10 includes a switch 200 configured to permit the user to selectively activate the forceps 10 in a variety of different orientations, i.e., multi-oriented activation. As can be appreciated, this simplifies activation. When the switch 200 is depressed, electrosurgical energy is transferred through one or more leads (e.g., 311 shown in FIGS. 10, 12 and 13) to the jaw members 110 and 120. Switch 200 may be disposed on another part of the forceps 10 (e.g., the fixed handle 50, rotatable member 82, etc.) or another location on the housing assembly 20.

[0052] FIG. 4 shows a schematic of an end effector assembly 400 that includes an electrically-insulative hinge 450 according to an embodiment of the present disclosure. End effector assembly 400 (also referred to herein as a “jaw assembly”) generally includes a pair of opposing jaw members 410 and 420. Jaw members 410 and 420 are pivotably mounted with respect to one another such that jaw member 410 pivots in a unilateral fashion from an open position to a closed position for grasping and manipulating tissue. Jaw members 410 and 420 shown in FIG. 4 are similar to the jaw members 110 and 120 of FIG. 1, respectively, and further description thereof is omitted in the interests of brevity.

[0053] As best shown in FIG. 7, the electrically-insulative hinge 450 is configured with one or more pivot-hole locators 454 to facilitate proper alignment of the jaw members 410 and 420 during assembly of the end effector assembly 400. Electrically-insulative hinge 450 is configured to electrically isolate the jaw members 410 and 420 from one another, and may be bonded or otherwise securely attached to either one of the jaw members. Electrically-insulative hinge 450 may be attached to the moveable jaw member 410 or the fixed jaw member 420 using any suitable material or bonding process.

[0054] In the embodiment shown in FIGS. 4 and 5, the electrically-insulative hinge 450 is attached to the moveable jaw member 410, e.g., using an adhesive material 415. Alternatively, the electrically-insulative hinge 450 may be attached to the fixed jaw member (e.g., 620, as shown in FIG. 6). In some embodiments, as shown in FIG. 5, the fixed jaw member 420 and the electrically-insulative hinge 450 affixed to the moveable jaw member 410 are spaced apart by a gap 416, e.g., to reduce friction and/or wear.

[0055] During use of the jaw assembly 400, the electrically-insulative hinge 450 maintains electrical isolation of the jaw members 410 and 420, permitting energy potential to flow through the tissue being treated before returning through the opposing jaw. For example, when the jaw members 410 and 420 are electrically isolated from one another, electrosurgical energy can be effectively transferred through tissue 1420 to form seal 1450 as shown in FIG. 15.

[0056] In the embodiment shown in FIGS. 4 and 5, the unilateral jaw assembly 400 includes the electrically-insulative hinge 450 and a pivot pin 403 connecting the jaw members 410 and 420 at their rotation point, allowing the movable jaw member 410 to rotate relative to the fixed jaw member 420. As cooperatively shown in FIGS. 4 and 5, the pivot pin 403 passes through the pin slot or opening 419 defined in the moveable jaw member 410 and is received by the pivot holes defined in the fixed jaw member 420 (e.g., similar to the pivot holes 101a, 101b defined in the fixed jaw member 120 shown in FIG. 12) and the apertures 451 (FIG. 12) defined in the pivot-hole locators 454 of the electrically-insulative hinge 450 such that the jaw members 410 and 420 are pivotably mounted with respect to one another. Alternatively, wherein both jaw members are movable, a bilateral end effector assembly (e.g., bilateral end effector assembly 800 shown in FIG. 8) includes an electrically-insulative hinge (e.g., 850 shown in FIG. 8) configured to provide electrical isolation of the jaw members.

[0057] As shown in FIGS. 5, 6 and 8, the presently-disclosed jaw assemblies and electrically-insulative hinge embodiments allow a pivot pin (e.g., 403 shown in FIG. 5, 603 shown in FIGS. 6, and 803 shown in FIG. 8) to be connected to one jaw member (e.g., 410 shown in FIG. 5, 610 shown in FIGS. 6, and 820 shown in FIG. 8) and to the electrically-insulative hinge (e.g., 450 shown in FIGS. 5 and 6, and 850 shown in FIG. 8) that is bonded or otherwise attached to the opposing jaw member. In either unilateral or bilateral end effector embodiments, by connecting the pivot pin, which may be formed of an electrically-conductive material, to one jaw member and not to the other jaw member but, instead, to the electrically-insulative hinge, the pivot pin will not defeat the electrical isolation of the jaw members.

[0058] As cooperatively shown in FIGS. 4 and 7, electrically-insulative hinge 450 includes a generally U-shaped body member 452 and two end portions 453a and 453b disposed at the opposite ends of the body member 452. The shape and size of the body member 452 and end portions 453a and 453b, which are described in more detail below, may be varied from the configuration depicted in FIGS. 4 through 7.

[0059] Electrically-insulative hinge 450 is configured with one or more pivot-hole locators 454, e.g., defined by the end portions 453a and/or 453b. In some embodiments, each of the end portions 453a and 453b includes an aperture 451 defined therein. Alternatively, only one of the end portions 453a or 453b includes an aperture 451 defined therein. Aperture 451 is configured to receive a portion of a pivot pin 403 therein. Electrically-insulative hinge 450 is formed from a suitable electrically-insulative material. Examples of electrically-insulative materials that may be suitable for forming the electrically-insulative hinge 450 include without limitation plastics, ceramic, glass or other non-conductive materials with desired properties. Electrically-insulative hinge 450 may be fastened to either one of the jaws by any suitable process including without limitation adhesive bonding, soldering, brazing, overmolding, mechanical interlock, snaps, bent tabs, screws or other mechanical fasteners, etc.

[0060] FIG. 6 shows a unilateral jaw assembly 600 that includes the electrically-insulative hinge 450, a pivot pin 603, and jaw members 610 and 620. In the embodiment shown in FIG. 6, the electrically-insulative hinge 450 is attached to the fixed jaw member 620, e.g., using an adhesive material 613. In some embodiments, the moveable jaw member 610 and the electrically-insulative hinge 450 that is attached to the fixed jaw member 620 are spaced apart by a gap 616, e.g., to reduce friction and/or wear.

[0061] FIG. 7 shows a schematic of a fixture 780 configured to releaseably hold the end effector assembly 600 of FIG. 6, such as during a fastening process, according to an embodiment of the present disclosure. Fixture 780 is configured to hold the jaw members 610 and 620 in proper alignment while the electrically-insulative hinge 450 is fastened and/or cured to the moveable jaw member 610 or the fixed jaw member 620. In some embodiments, the jaw members 610 and 620 are self-aligned by pre-assembling the jaw components including the jaw members 610 and 620, the electrically-insulative hinge 450 and the pivot pin 603. Any remaining degrees of freedom are then constrained by the holding fixture 780 until the bond between the electrically-insulative hinge 450 and the fixed jaw member 620 (shown in FIG. 6) or the bond between the electrically-insulative hinge 450 and the moveable jaw member 610 is completed. In the embodiment shown in FIG. 7, the fixture 780 serves to hold the sealing surface of the jaw member 610 directly against the sealing surface of the jaw member 620 with desired jaw gap controlled by gap features on the jaw members 610, 620 and/or with shims used during assembly, which may be a critical alignment, while the bond is made. When the bonding process is completed, the holding fixture 780 may be removed from the jaw assembly 600. It will be appreciated that additional manufacturing steps may be undertaken after the bonding process is completed, prior to the release of the jaw assembly 600 from the fixture 780. In some embodiments, after the bonding process is completed, the pivot pin 603 may be removed and the jaws separated, if desired, for assembly or further processing.

[0062] In some embodiments, the fixture 780 includes a shaft 782, a first leg member 783 disposed at a first end 781a of the shaft 782, and a second leg member 785 disposed at a second end 781b of the shaft 782. First leg member 783 and the second leg member 785 may extend in a substantially perpendicular direction away from the shaft 782, such that the fixture 780 may have a generally U-like shape. In some embodiments, the shaft 782, the first leg member 783 and the second leg member 785 are integrally formed. In some embodiments, the first leg member 783 includes a first tip portion 784 and the second leg member 785 includes a second tip portion 786. In some embodiments, the shaft 782, the first leg member 783, the first tip portion 784, the second leg member 785 and the second tip portion 786 may be configured such that the fixture 780 has a generally C-like shape. Fixture 780 could be formed in a variety of shapes suitable to constrain the jaw members adequately during completion of the bonding process. Fixture 780 may be made from metal, plastic, ceramic and/or other suitable materials with desired properties, e.g., machinability, flexibility, moldability, temperature resistance, chemical resistance, etc. Fixture 780 and/or the jaw members may include features to enable quick, accurate, secure and reliable holding, including without limitation flats, slots, holes, grooves, recesses, pins, stops or any other suitable features that provides alignment and/or mating engagement of the fixture 780 to the jaw members. In some embodiments, either one (or both) of the jaw members may include one or more grooves or recesses defined therein configured and disposed to accept or matingly engage with one or more edge portions or protrusions formed on the first tip portion 784 and/or the second tip portion 786 of the fixture 780.

[0063] FIG. 8 shows a bilateral end effector assembly 800 that includes an electrically-insulative hinge 850 that is configured to provide electrical isolation of the first and second jaw members 810 and 820. Electrically-insulative hinge 850 is formed from a suitable electrically-insulative material, and includes an aperture defined therein. FIG. 9 is a side-view of the end effector assembly 800 illustrating the second jaw member 820, pivot pin 803, and electrically-insulative hinge 850.

[0064] In the embodiment shown in FIGS. 8 and 9, the electrically-insulative hinge 850 is bonded or otherwise securely attached to the second jaw member 820, e.g., using an adhesive material 813. Alternatively, the electrically-insulative hinge 850 may be attached to the first jaw member 810. Electrically-insulative hinge 850 may be attached to the first jaw member 810 or the second jaw member 820 using any suitable material or bonding process.

[0065] As shown in FIG. 8, the pivot pin 803 is received by an aperture defined in the electrically-insulative hinge 850 and a pivot hole defined in the first jaw member 810. In some embodiments, the pivot pin 803 is secured by a fastener 804, e.g., a pin, cap, shoulder, rivet, swage, nut, etc. In some embodiments, the first jaw member 810 and the electrically-insulative hinge 850 that is attached to the second jaw member 820 are spaced apart by a gap 816, e.g., to reduce friction and thereby minimize wear.

[0066] As shown in FIGS. 10 and 12, jaw member 110 also includes a jaw housing 116 that includes an insulative substrate or insulator 114 and an electrically-conductive surface 112. Insulator 114 is configured to securely engage the electrically-conductive sealing surface 112. This may be accomplished by stamping, by overmolding, by overmolding a stamped electrically-conductive sealing plate and/or by overmolding a metal injection molded seal plate. For example and as shown in FIG. 12, the electrically-conductive sealing plate 112 includes a series of upwardly extending flanges 111a and 111b that are designed to matingly engage the insulator 114. Insulator 114 includes a shoe-like interface 107 disposed at a distal end thereof which is configured to engage the outer periphery 116a of the housing 116 in a slip-fit manner. The shoe-like interface 107 may also be overmolded about the outer periphery of the jaw 110 during a manufacturing step. Lead 311 terminates within the shoe-like interface 107 at the point where the lead 311 electrically connects to the sealing plate 112. The movable jaw member 110 is configured with a wire channel 113 to guide the cable lead 311 into electrical continuity with the sealing plate 112.

[0067] As best shown in the exploded view of FIG. 12, jaw members 110 and 120 are pivotably mounted with respect to one another such that the jaw member 110 pivots in a unilateral fashion from a first open position to a second closed position for grasping and manipulating tissue 1420 (shown in FIG. 14). Fixed jaw member 120 includes a pair of proximal, upwardly extending flanges 125a and 125b that define a cavity 121 configured to receive the pivot flange 118 of the movable jaw member 110 therein. Each of the flanges 125a and 125b includes an aperture 101a and 101b, respectively, defined therethrough that secures the pivot pin 103 on opposite sides of a pin slot or opening 119 disposed within the jaw member 110.

[0068] Jaw member 110 includes a pivot flange 118. Protrusion 117 extends from the pivot flange 118 and includes an arcuately-shaped inner surface 111 configured to matingly engage the aperture 62 of sleeve 60 upon retraction thereof. Pivot flange 118 includes an opening 119 defined therein that is configured to allow the pivot pin 103 to pass therethrough, e.g., to allow jaw member 110 to rotate relative to jaw member 120 upon retraction of the reciprocating sleeve 60. In some embodiments, the pivot pin 103 mounts to the electrically-insulative hinge 450 through a pair of apertures 451 defined therein and mounts to the stationary jaw member 120 through a pair of apertures 101a and 101b disposed within a proximal portion of the jaw member 120.

[0069] Jaw member 120 fixes to the end of a rotatable tube 160 (shown in FIGS. 2 and 3) which is part of the rotatable assembly 80 such that rotation of the tube 160 will impart rotation to the end effector assembly 100. As shown in FIG. 2, the distal end of the tube 160 is generally C-shaped to include two upwardly extending flanges 162a and 162b that define a cavity 165 for receiving the proximal end of the fixed jaw member 120 inclusive of C-shaped cuff 170 and slide pin 171. The tube cavity 165 retains and secures the jaw member 120 in a friction-fit manner; however, the jaw member 120 may be welded to the tube 160 depending upon a particular purpose. Tube 160 also includes an inner cavity 169 (shown in FIG. 3) defined therethrough that reciprocates the knife assembly 180 upon distal activation thereof and an elongated guide rail 163 that guides the knife assembly 140 during distal activation. The proximal end of tube 160 includes a laterally-oriented slot 168 that is designed to interface with the rotating assembly 80, as described in the above-mentioned, commonly-assigned U.S. Pat. Nos. 7,150,097, 7,156,846, 7,597,693 and 7,771,425.

[0070] Jaw member 120 includes a rear C-shaped cuff 170 having a slot 177 defined therein which is configured to receive a slide pin 171. Slide pin 171 includes a slide rail 176 that extends substantially the length thereof, configured to slide into friction-fit engagement within slot 177. A pair of chamfered plates 172a and 172b extends generally radially from the slide rail 176 and include a radius that is substantially the same radius as the outer periphery of the rotatable tube 160 such that the shaft 12 can encompass each of the same upon assembly. The chamfered plates 172a and 172b also form a wire channel 175 that is configured to guide the cable lead 311 from the tube 160 and into the movable jaw member 110 (see FIG. 12). Lead 311 carries a first electrical potential to movable jaw 110. The electrically-conductive surface 112 and the insulator 114, when assembled, include a longitudinally-oriented channel 115a defined therethrough for reciprocation of the knife blade 185.

[0071] Jaw member 120 includes similar elements to jaw member 110 such as jaw housing 126 having an insulator 124 and an electrically-conductive sealing surface 122 that is configured to securely engage the insulator 124. Likewise, the electrically-conductive surface 122 and the insulator 124, when assembled, include a longitudinally-oriented channel 115b defined therethrough for reciprocation of the knife blade 185. Knife channel 115 (made up of half channels 115a and 115b) is blocked when the jaws members 110 and 120 are opened and aligned for distal activation when the jaw members 110 and 120 are closed.

[0072] Jaw member 120 is connected to a second electrical potential through tube 160 which is connected at its proximal end to a lead (not shown). Fixed jaw 120 may include a fuse clip, spring clip or other electro-mechanical connection. In some embodiments, at least one jaw member, e.g., 120, includes a stop member 750 that limits the movement of the two opposing jaw members 110 and 120 relative to one another. Stop member embodiments and internal electrical connections of the forceps 10 are described in the above-mentioned, commonly-assigned U.S. Pat. Nos. 7,150,097, 7,156,846, 7,597,693 and 7,771,425. As best shown in FIG. 2, the rotatable tube 160 includes an elongated guide slot 167 disposed in an upper portion thereof and configured to carry lead 311 therealong.

[0073] Proximal movement of the tube 60 engages detent 117 to pivot the jaw member 110 to a closed position. It is understood from FIG. 12 that the jaw member 120 is stationary.

[0074] FIG. 14 shows the end effector assembly 100 of FIG. 1 shown grasping tissue 1420. In some embodiments, the end effector assembly 100 may include a gap distance “G” between opposing sealing surfaces 112 during sealing, e.g., in the range from about 0.001 inches to about 0.006 inches. In some embodiments, the end effector assembly 100 includes a gap distance “G” between opposing sealing surfaces 112 during sealing that ranges from about 0.002 to about 0.003 inches. As shown in FIG. 16, the forceps 10 is insertable through a cannula 500 into a patient's body for use during a procedure.

[0075] As energy is being selectively transferred to the end effector assembly 100, across the jaw members 110 and 120 and through the tissue 1420, a tissue seal 1450 forms isolating two tissue halves 1420a and 1420b (see FIG. 15). The knife assembly 180 which, when activated via the trigger assembly 70, progressively and selectively divides the tissue 1420 along a tissue plane in a precise manner to divide the tissue 1420 into two sealed halves (not shown). Once the tissue 1420 is divided into tissue halves, the jaw members 110 and 120 may be opened by re-initiation or re-grasping of the handle 40.

[0076] Hereinafter, methods of manufacturing an end effector assembly are described with reference to FIG. 17 through 19. It is to be understood that the steps of the methods provided herein may be performed in combination and in a different order than presented herein without departing from the scope of the disclosure.

[0077] FIG. 17 is a flowchart illustrating a method of manufacturing an end effector assembly 100 according to an embodiment of the present disclosure that includes a first jaw member 110 and a second jaw member 120. In some embodiments, the first and second jaw members 110, 120 are configured to be pivotably mounted with respect to one another.

[0078] In step 1710, a first jaw member 110 is provided. The first jaw member 110 includes a pin slot or opening 119 defined therethrough.

[0079] In step 1720, a second jaw member 120 is provided. The second jaw member 120 includes one or more pivot holes 101a, 101b defined therethrough.

[0080] In step 1730, an electrically-insulative hinge 450 is provided that is configured to electrically isolate the jaw members from one another. The electrically-insulative hinge 450 is formed from a suitable electrically-insulative material. The electrically-insulative hinge 450 includes one or more pivot-hole locators 454 defined therein, and may take any suitable shape.

[0081] In some embodiments, the electrically-insulative hinge 450 includes a generally U-shaped body member 452 and two end portions 453a, 453b disposed at the opposite ends of the body member 452. One or more of the end portions 453a, 453b includes an aperture 451 defined therein configured to receive a portion of a pivot pin 103 therein. In some embodiments the one or more pivot-hole locators 454 are defined by the one or more end portions 453a, 453b that include the aperture 451.

[0082] In step 1740, the electrically-insulative hinge 450 is attached to the first jaw member 110 such that the one or more pivot-hole locators 454 align with the one or more pivot holes 101a, 101b of the second jaw member 120. The electrically-insulative hinge 450 may be bonded or otherwise securely attached the first jaw member 110 using any suitable material or bonding process, e.g., adhesive bonding, soldering, brazing, overmolding, mechanical interlock, snaps, bent tabs, etc.

[0083] In step 1750, the first and second jaw members 110, 120 are pinned via the one or more pivot-hole locators 454 and the one or more pivot holes 101a, 101b such that the first and second jaw members 110, 120 are pivotably mounted with respect to one another.

[0084] FIG. 18 is a flowchart illustrating a method of manufacturing an end effector assembly 100 according to an embodiment of the present disclosure. In step 1810, a first jaw member 110 is provided. The first jaw member 110 includes a pin slot or opening 119 defined therethrough.

[0085] In step 1820, a second jaw member 120 is provided. The second jaw member 120 includes one or more pivot holes 101a, 101b defined therethrough.

[0086] In step 1830, an electrically-insulative hinge 450 is provided that is configured to electrically isolate the jaw members from one another. The electrically-insulative hinge 450 includes one or more pivot-hole locators 454 having an aperture 451 defined therein.

[0087] In step 1840, the electrically-insulative hinge 450 is attached to the first jaw member 110 such that the aperture 451 of the one or more pivot-hole locators 454 aligns with the one or more pivot holes 101a, 101b of the second jaw member 120. The electrically-insulative hinge 450 may be bonded or otherwise securely attached the first jaw member 110 using any suitable material or bonding process.

[0088] In step 1850, a pivot pin 103 is provided. The pivot pin 103 is configured to pass through the pin slot or opening 119 and to be received by the one or more pivot holes 101a, 101b.

[0089] In step 1860, the pivot pin 103 is inserted into the one or more pivot holes 101a, 101b and the aperture 451 of the one or more pivot-hole locators 454 such that the first and second jaw members 110, 120 are pivotably mounted with respect to one another.

[0090] FIG. 19 is a flowchart illustrating a method of manufacturing an end effector assembly 100 according to an embodiment of the present disclosure. In step 1910, a first jaw member 110 is provided. The first jaw member 110 includes a pin slot or opening 119 defined therethrough.

[0091] In step 1920, a second jaw member 120 is provided. The second jaw member 120 includes one or more pivot holes 101a, 101b defined therethrough.

[0092] In step 1930, an electrically-insulative hinge 450 is provided that is configured to electrically isolate the jaw members from one another. The electrically-insulative hinge 450 includes one or more pivot-hole locators 454 defined therein.

[0093] In step 1940, the electrically-insulative hinge 450 is attached to the first jaw member 110 such that the one or more pivot-hole locators 454 align with the one or more pivot holes 101a, 101b of the second jaw member 120. The electrically-insulative hinge 450 may be bonded or otherwise securely attached the first jaw member 110 using any suitable material or bonding process.

[0094] In step 1950, a holding fixture 780 is provided. The fixture 780 is configured to releaseably hold the first jaw member 110 in contact with the second jaw member 120. In some embodiments, the fixture 780 is configured to hold the first and second jaw members 110, 120 in proper alignment while the electrically-insulative hinge 450 is fastened and/or cured to the first jaw member 110 (or the second jaw member 120). In some embodiments, the fixture 780 is configured to hold the sealing surface 112 of the first jaw member 110 directly against the sealing surface 122 of the second jaw member 120 in proper alignment while the electrically-insulative hinge 450 is fastened and/or cured to the first jaw member 110 (or the second jaw member 120).

[0095] In step 1960, a pivot pin 103 is provided. In some embodiments, the pivot pin 103 is configured to pass through the pin slot or opening 119 and to be received by the one or more pivot holes 101a, 101b.

[0096] In step 1970, the fixture 780 is releasably coupled to the first and second jaw members 110, 120. In some embodiments, the jaw member 110 and/or the jaw member 120 may include one or more grooves or recesses defined therein configured and disposed to accept or matingly engage with one or more edge portions or protrusions formed on a first and tip portion 784 and/or a second tip portion 786 of the fixture 780.

[0097] In step 1980, the pivot pin 103 is inserted into the one or more pivot holes 101a, 101b and the one or more pivot-hole locators 454 such that the first and second jaw members 110, 120 are pivotably mounted with respect to one another.

[0098] In some embodiments, after the pivot pin 103 is inserted into the one or more pivot holes 101a, 101b and the one or more pivot-hole locators 454, in step 1980, and after the bond between the electrically-insulative hinge 450 and the first jaw member 110 is completed, the first and second jaw members 110, 120 are released from the fixture 780, in step 1990. It will be appreciated that additional manufacturing steps may be undertaken after the step 1980, prior to the release of the first and second jaw members 110, 120 from the fixture 780.

[0099] The presently-disclosed bipolar forceps is capable of directing energy into tissue, and may be suitable for use in a variety of procedures and operations. The above-described bipolar forceps embodiments may utilize both mechanical clamping action and electrical energy to effect hemostasis by heating tissue and blood vessels to coagulate, cauterize, cut and/or seal tissue. The jaw assemblies may be either unilateral or bilateral. The above-described bipolar forceps embodiments may be suitable for utilization with endoscopic surgical procedures and/or hand-assisted, endoscopic and laparoscopic surgical procedures. The above-described bipolar forceps embodiments may be suitable for utilization in open surgical applications.

[0100] Although embodiments have been described in detail with reference to the accompanying drawings for the purpose of illustration and description, it is to be understood that the inventive processes and apparatus are not to be construed as limited thereby. It will be apparent to those of ordinary skill in the art that various modifications to the foregoing embodiments may be made without departing from the scope of the disclosure.