Patent Publication Number: US-2020275969-A1

Title: Treatment instrument and manufacturing method of treatment instrument

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This is a Continuation Application of PCT Application No. PCT/JP2017/042035, filed on Nov. 22, 2017, the entire contents of which are incorporated herein by reference. 
    
    
     BACKGROUND 
     1. Technical Field 
     The exemplary embodiments relate generally to a treatment instrument and a manufacturing method of the treatment instrument. 
     2. Description of the Related Art 
     A treatment instrument capable of grasping a treatment target between a pair of jaws (grasping pieces). In this treatment instrument, an electrically conductive plate (electrode) is provided in each of the jaws, and electric energy (high-frequency electric power) is supplied to each conductive plate, thereby allowing a high-frequency current to flow in the treatment target grasped between the electrically conductive plates. 
     SUMMARY 
     According to one aspect, a treatment instrument including: an electrically conductive plate including a treating surface configured to contact a treatment target, and a back surface facing an opposite side of the treating surface, the electrically conductive plate extending along a longitudinal axis; an electric component arranged on the back surface of the electrically conductive plate, the electric component being electrically independent from the electrically conductive plate; a holder supporting the electrically conductive plate and the electric component from a side of the back surface; and a connector made of a thermoplastic resin, the connector being arranged on either side of and spaced from the electric component in a width direction of the treatment instrument intersecting with the longitudinal axis, and the connector stationarily fixing each side end of the electrically conductive plate to the holder in the width direction. 
     According to one another aspect, a manufacturing method of a treatment instrument, the method including: forming an electrically conductive plate, the electrically conductive plate including a treating surface configured to contact a treatment target, and a back surface facing an opposite side of the treating surface, the electrically conductive plate extending along a longitudinal axis; arranging an electric component on the back surface of the electrically conductive plate, the electric component being electrically independent from the electrically conductive plate; forming a holder supporting the electrically conductive plate and the electric component from a side of the back surface; and softening or deforming a portion made of a thermoplastic resin in the holder by applying heat to the portion, or injecting a heated and softened thermoplastic resin, in a region distant from the electric component in width direction intersecting with the longitudinal axis, in a state in which the electrically conductive plate is supported by the holder; and cooling and hardening the deformed portion of the holder or the injected thermoplastic resin so as to stationarily fix each side end of the electrically conductive plate to the holder in the width direction. 
     Advantages of the exemplary embodiments will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the exemplary embodiments. The advantages may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING 
       The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments, and together with the general description given above and the detailed description of the embodiments given below. 
         FIG. 1  is a schematic diagram of a treatment system of a first embodiment. 
         FIG. 2  is a schematic diagram of a distal portion of a shaft and an end effector of the first embodiment. 
         FIG. 3  is a cross-sectional view schematically showing the end effector of the first embodiment in a cross section perpendicular or substantially perpendicular to a longitudinal direction. 
         FIG. 4  is a schematic diagram explaining a process of forming connectors in manufacturing of either jaw in the first embodiment. 
         FIG. 5  is a cross-sectional view schematically showing either jaw according to a first modification of the first embodiment in a cross section perpendicular or substantially perpendicular to a longitudinal direction. 
         FIG. 6  is a schematic diagram explaining a process of forming connectors in manufacturing of either jaw according to the first modification of the first embodiment. 
         FIG. 7  is a cross-sectional view schematically showing either jaw according to a second modification of the first embodiment in a cross section perpendicular or substantially perpendicular to a longitudinal direction. 
         FIG. 8  is a schematic diagram showing an electrically conductive plate provided on either jaw according to a third modification of the first embodiment. 
         FIG. 9  is a cross-sectional view schematically showing a structure of a connector and its vicinity in either jaw according to a third modification of the first embodiment. 
         FIG. 10  is a schematic diagram showing a distal portion of a shaft and an end effector of a fourth modification of the first embodiment. 
         FIG. 11  is a schematic diagram explaining a process of attaching an electrically conductive plate and a block to a holder in manufacturing of either jaw in the fourth modification of the first embodiment. 
         FIG. 12  is a schematic diagram showing an electric conductive plate and a block provided on either jaw according to a fifth modification of the first embodiment. 
         FIG. 13  is a cross-sectional view schematically showing either jaw according to a second embodiment in a cross section perpendicular or substantially perpendicular to a longitudinal direction. 
         FIG. 14  is a schematic diagram explaining a process of forming connectors in manufacturing of either jaw in the second embodiment. 
         FIG. 15  is a cross-sectional view schematically showing a structure of a connector and its vicinity in either jaw according to a modification of the second embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     First Embodiment 
     A first embodiment will be described with reference to  FIGS. 1 to 4 .  FIG. 1  shows a treatment system  1  of the present embodiment. As shown in  FIG. 1 , the treatment system  1  includes a treatment instrument  2  and an electric power supply apparatus  3 . The treatment instrument  2  is detachably connected to the electric power supply apparatus  3  via a cable  5 . The treatment instrument  2  includes a cylindrical shaft (sheath)  6 , a holdable housing  7 , and an end effector  8 . The shaft  6  has a longitudinal axis C as a center axis. Herein, one side along the longitudinal axis C is defined as a distal side (arrow C 1  side), and a side opposite to the distal side is defined as a proximal side (arrow C 2  side). The shaft  6  extends along the longitudinal axis C from the proximal side to the distal side, and the housing  7  is coupled to the proximal side of the shaft  6 . The end effector  8  is connected to the distal side of the shaft  6 , and extends from the distal portion of the shaft  6  toward the distal side. The end effector  8  extends along the longitudinal direction of the end effector  8 , from the proximal portion toward the distal portion. 
     The housing  7  includes a grip  11  that extends in a direction intersecting with the longitudinal axis C. To this housing  7 , a handle  12  is pivotably attached. When the handle  12  pivots relative to the housing  7 , the handle  12  opens or closes with respect to the grip  11 . In the present embodiment, one end of the cable  5  is connected to the housing  7 . The other end of the cable  5  is detachably connected to the electric power supply apparatus  3 . An operation apparatus  10 , such as a foot switch, is electrically connected to the electric power supply apparatus  3 . In the operation apparatus  10 , an operation to cause the electric power supply apparatus  3  to output electric energy to the treatment instrument  2  is input. In one example, instead of or in addition to the operation apparatus  10  provided separately from the treatment instrument  2 , an operating button, etc. attached to the housing  7 , etc. of the treatment instrument  2  is provided as an operation apparatus. With this operation apparatus attached to the treatment instrument  2 , an operation to cause the electric power supply apparatus  3  to output electric energy to the treatment instrument  2  is input. 
       FIG. 2  shows configurations of the distal portion of the shaft  6  and the end effector  8 . As shown in  FIGS. 1 and 2 , the end effector  8  includes a pair of jaws (grasping pieces)  15  and  16 . Each of the jaws  15  and  16  continuously extends from the proximal portion to the distal portion of the end effector  8 , along the longitudinal direction of the end effector  8 . The jaws  15  and  16  as a pair can close and open with respect to each other. In one example, one of the jaws  15  and  16  is integrated into the shaft  6  or stationarily fixed to the shaft  6 , and the other of the jaws  15  and  16  is pivotably attached to the shaft  6 . In another example, both of the jaws  15  and  16  are pivotably attached to the shaft  6 . The opening and closing directions (the directions indicated by arrows Y 1  and Y 2 ) of the end effector  8 , in other words, the moving directions of the jaws  15  and  16  in the opening and closing movements of the end effector  8 , intersect with (are perpendicular or substantially perpendicular to) the longitudinal direction of the end effector  8 . 
     In the inside of the housing  7 , the proximal portion of a movable member  17  is coupled to the handle  12 . The movable member  17  is movable along the longitudinal axis C relative to the shaft  6  and the housing  7 . The distal end of the movable member  17  is coupled to at least one of the jaws  15  and  16 . By opening or closing the handle  12  with respect to the grip  11 , the movable member  17  moves along the longitudinal axis C. Thus, at least one of the jaws  15  and  16  pivots, and the jaws  15  and  16  open or close with respect to each other. When they are closed with respect to each other, it is thus possible to grasp a treatment target, such as living tissue, between the jaws  15  and  16 . In one example, an operation member, such as a rotative knob, etc., is attached to the housing  7 . When an operation is input at the operation member, the end effector  8  and the shaft  6  together rotate around the longitudinal axis C relative to the housing  7 . 
     In another example, an operation member, such as a dial, is provided in the housing  7 , and the end effector  8  bends or curves with respect to the shaft  6  and the longitudinal axis C in response to an operation input at the operation member. In this example, a relaying member (not shown) provided in the end effector  8  is attached to the shaft  6  in a bendable or curvable manner. One of the jaws  15  and  16  is pivotably attached to the relaying member. The other of the jaws  15  and  16  may be integrated into, stationarily fixed to, or pivotably attached to the relaying member. 
       FIG. 3  shows the end effector  8  in a cross section perpendicular or substantially perpendicular to the longitudinal direction (a cross section intersecting with the longitudinal direction).  FIG. 3  shows a state where the jaws  15  and  16  are closed with respect to each other. Herein, in the end effector  8 , suppose the direction intersecting with (perpendicular or substantially perpendicular to) the longitudinal direction, and intersecting with (perpendicular or substantially perpendicular to) the opening and closing directions of the end effector  8  (the directions indicated by arrows Y 1  and Y 2 ) is “width direction” (the direction indicated by arrows W 1  and W 2 ). In one example, in each of the jaws  15  and  16 , the dimension in the longitudinal direction is greater than the dimension in the width direction. As shown in  FIGS. 2 and 3 , in the present embodiment, the jaw  15  includes a holder  21  and an electrically conductive plate (electrode)  22 . Each of the holder  21  and the electrically conductive plate  22  continuously extends from the proximal portion to the distal portion of the jaw  15 , in the longitudinal direction of the end effector  8 . The holder  21  is made of a resin, etc., having thermal resistance and electric insulation properties, for example. In one example, the holder  21  may be made by insert molding, etc. so as to encapsulate a core made of a metal, etc. with a resin. The electrically conductive plate  22  is made of a metal, etc. having electrical conductivity. 
     The jaw  15  includes a grasping surface (opposing surface)  23  opposing to the other jaw  16 , and a back surface  25  facing the opposite side of the grasping surface  23 . Each of the grasping surface  23  and the back surface  25  continuously extends from the proximal portion to the distal portion of the jaw  15 , along the longitudinal direction of the end effector  8 . In the present embodiment, the holder  21  and the electrically conductive plate  22  constitute the grasping surface  23 , and the holder  21  constitutes the back surface  25 . In a state in which a treatment target is grasped between the jaws  15  and  16 , the treatment target is in contact with the grasping surface  23 . On the grasping surface  23 , an abutting portion  26  to which the jaw  16  can abut while the jaws  15  and  16  are closed with respect to each other is provided. The abutting portion  26  is formed by the holder  21 , and is made of a material having electric insulation properties. In the present embodiment, the abutting portion  26  continuously extends from the proximal portion to the distal portion of the jaw  15 , in the longitudinal direction of the end effector  8 , and is formed in the center of the jaw  15  according to the width direction of the end effector  8 . On the grasping surface  23 , the electrically conductive plates  22  are provided on both sides of the abutting portion  26  in the width direction of the end effector  8 . 
     In a not-shown example, the holder  21  has a frame made of a metal, etc. and having appropriate rigidity, and this frame constitutes the back surface  25 . When the frame has electrical conductivity, the outer peripheral surface of the frame is entirely coated with a material having electric insulation properties, such as polytetrafluoroethylene (PTFE). 
     The other jaw  16  has a longitudinal axis C′ as a center axis, and extends along the longitudinal axis C′, from its proximal end to its distal end. When the jaws  15  and  16  are closed with respect to each other, the longitudinal axis C′ of the jaw  16  is parallel or substantially parallel to the longitudinal direction of the end effector  8 . The opening and closing directions of the end effector  8  intersect with (are perpendicular or substantially perpendicular to) the longitudinal axis C′. Furthermore, the width direction of the end effector  8  intersect with (are perpendicular or substantially perpendicular to) the longitudinal axis C′, and intersect with (are perpendicular or substantially perpendicular to) the opening and closing directions of the end effector  8 . The jaw  16  includes an electrically conductive plate (blade)  31 , a heater  32  which is an electric component, a holder  33 , and connectors  35 A and  35 B. Each of the electrically conductive plate  31 , the heater  32 , the holder  33 , and the connectors  35 A and  35 B continuously extends from the proximal portion to the distal portion of the jaw  16 , in a direction along the longitudinal direction C′ (the longitudinal direction of the end effector  8 ). 
     The jaw  16  includes a treating surface (opposing surface)  41  opposing to the grasping surface  23 , and a back surface  42  facing the opposite side of the treating surface  41 . Each of the treating surface (grasping surface)  41  and the back surface  42  continuously extends from the proximal portion to the distal portion of the jaw  16 , in the direction along the longitudinal axis C′ (the longitudinal direction of the end effector  8 ). In the present embodiment, the electrically conductive plate  31  constitutes the treating surface  41 , and the holder  33  constitutes the back surface  42 . For this reason, in the present embodiment, the jaw  15  is arranged in such a manner that it faces the treating surface  41  of the electrically conductive plate  31 , and the space between the electrically conductive plate  31  and the jaw  15  can be open or closed. In a state in which a treatment target is grasped between the jaws  15  and  16 , the treatment target is in contact with the treating surface  41 . 
     The electrically conductive plate  31  is made of a metal, etc. having electrical conductivity; in the present embodiment, the electrically conductive plate  31  is made of a material having properties of high thermal conductivity (a high thermal conductivity rate). In the electrically conductive plate  31 , a projection  43  that projects toward the jaw  15  side is formed. At the projection  43 , the treating surface  41  projects toward the jaw  15  side, compared to the portions other than the projection  43 . In the present embodiment, the projection  43  continuously extends from the proximal portion to the distal portion of the jaw  16  (the electrically conductive plate  31 ) in the direction along the longitudinal axis C′, and is formed in the center of the jaw  16  according to the width direction of the end effector  8 . In the treating surface  41 , the inclined surfaces  45 A and  45 B are formed on respective sides of the projection  43  in the width direction of the end effector  8 . The inclined surfaces  45 A and  45 B are formed by the electrically conductive plate  31 , and continuously extend from the proximal portion to the distal portion of the jaw  16  (the electrically conductive plate  31 ) in the direction along the longitudinal axis C′. Each of the inclined surfaces  45 A and  45 B is inclined in a state that the surface extends toward the side on which the jaw  16  opens as the surface becomes distant from the projection  43  in the width direction. The projection  43  may be formed with an acute or obtuse angle. 
     In a state where the jaws  15  and  16  are closed to each other, the projection  43  of the electrically conductive plate  31  is abutted to the abutting portion  26  of the jaw  15 . However, even when the electrically conductive plate  31  is abutted to the abutting portion  26 , the electrically conductive plate  31  is located at a distance from the electrically conductive plate  22  of the jaw  15  and does not come into contact with the electrically conductive plate  22 . For this reason, the contact between the electrically conductive plates  22  and  31  can be effectively prevented. 
     The electrically conductive plate  31  includes a back surface (plate back surface)  46  facing the opposite side of the treating surface  41 . The back surface  46  faces the side on which the jaw  16  opens. The heater  32  is provided on the back surface  46 , and is stationarily fixed to the electrically conductive plate  31  on the back surface  46 . In the present embodiment, the heater  32  is provided in the center of the jaw  16  in the width direction of the end effector  8 . The dimension B 1  of the heater  32  in the width direction of the end effector  8  is smaller than the dimension B 2  of the electrically conductive plate  31  in the width direction of the end effector  8 . Furthermore, the dimension B 1  is smaller than the dimension B 3  of the treating surface  41  in the width direction of the end effector  8 . The heater  32  is electrically insulated from the electrically conductive plate  31  by an insulating layer (not shown). For this reason, the heater  32  which is an electric component is electrically independent from the electrically conductive plate  31 . 
     In the present embodiment, upon an input of an operation at the operation apparatus  10 , high-frequency electric power is output from the electric power supply apparatus  3  to the electrically conductive plates  22  and  31  as electric energy. Thus, the electrically conductive plates  22  and  31  function as electrodes having electric potentials differing from each other. In a state in which a treatment target is grasped between the jaws  15  and  16 , when electric energy is supplied to the electrically conductive plates  22  and  31 , a high-frequency current flows between the electrically conductive plates  22  and  31  via the grasped treatment target, and the high-frequency current is thereby applied to the treatment target. 
     In the present embodiment, when an operation is input at the operation apparatus  10 , direct current electric power or alternating current electric power is output from the electric power supply apparatus  3  to the heater  32 . At this time, the electric energy is supplied to the heater  32  through an electric path which is independent from an electric path for supplying electric energy to the electrically conductive plates  22  and  31 . When the electric energy is supplied to the heater  32 , the electric energy is converted into thermal energy due to electric resistance of the heater  32 , and heat is thereby generated. The heat generated in the heater  32  is transferred to the treating surface  41  via the electrically conductive plate  31 . In a state in which the treatment target is grasped between the jaws  15  and  16 , when the electric energy is supplied to the heater  32 , the heat generated by the heater  32  is applied to the treatment target from the treating surface  41 . 
     The holder  33  supports the electrically conductive plate  31  from the back surface  46  side, namely, the side on which the jaw  16  opens. In the present embodiment, the holder  33  includes a core member  51  made of a metal, etc., and a coating  52  that coats the core member  51 . Each of the core member  51  and the coating  52  continuously extends from the proximal portion tow the distal portion of the jaw  16  (holder  33 ) in a direction along the longitudinal axis C′. The coating  52  is made of a material having thermal resistance and electric insulation properties, and properties of low thermal conductivity (a low thermal conductivity rate). Accordingly, the coating  52  of the holder  33  has lower thermal conductivity than that of the electrically conductive plate  31 . The coating  52  is formed by insert molding (injection molding) wherein a resin is inserted into the core member  51 , for example. In one example, the coating  52  is formed by a resin with glass bubbles added to it. In another example, a foaming resin, in other words, a porous resin, forms the coating  52 . 
     The coating  52  includes a supporting projection  53  projecting toward the electrically conductive plate  31 , namely the side on which the jaw  16  closes. In the present embodiment, the supporting projection  53  continuously extends from the proximal portion to the distal portion of the jaw  16  (holder  33 ), in the longitudinal direction of the end effector  8 , and is formed in the center of the jaw  16  according to the width direction of the end effector  8 . The electrically conductive plate  31  is supported by the supporting projection  53  from the back surface  46  side, and the supporting projection  53  is abutted to the back surface  46  of the electrically conductive plate  31 . 
     On the projection end surface of the supporting projection  53 , a mating concave portion  55  is formed in such a manner that its concave portion is concaved toward the side on which the jaw  16  opens. In the present embodiment, the mating concave portion  55  continuously extends from the proximal portion to the distal portion of the jaw  16  (holder  33 ), in the longitudinal direction of the end effector  8 , and is formed in the center of the supporting projection  53  according to the width direction of the end effector  8 . The heater  32  stationarily fixed to the back surface  46  of the electrically conductive plate  31  fits into the mating concave portion  55 , and engages the mating concave portion  55 . For this reason, in the jaw  16 , the heater  32  is arranged between the electrically conductive plate  31  and the holder  33  in the opening and closing directions of the end effector  8 . Since the coating of the holder  33  is made of a material having low thermal conductivity as described above, transfer of the heat generated in the heater  32  and Joule heat caused by a high-frequency current to the back surface  42  of the jaw  16  is difficult. For this reason, the increase of a temperature of the back surface  42  in the jaw  16  due to the heat of the heater  32  and the Joule heat caused by the high-frequency current can be effectively prevented. 
     In the jaw  16 , a connector (first connector)  35 A is provided on one side relative to the supporting projection  53  of the holder  33  in the width direction, and a connector (second connector)  35 B is provided on the other side relative to the supporting projection  53  in the width direction. For this reason, the supporting projection  53  is interposed between the connectors  35 A and  35 B according to the width direction, and the connector  35 A is provided on the opposite side of the connector  35 B with respect to the longitudinal axis C′ in the width direction. Each of the connectors  35 A and  35 B is arranged at a distance from the heater  32  toward an outer side in the width direction of the end effector  8 , and is stationarily fixed to the holder  33 . One end of the electrically conductive plate  31  in the width direction is stationarily fixed to the holder  33  by the connector  35 A. And the other end of the electrically conductive plate  31  in the width direction is stationarily fixed to the holder  33  by the connector  35 B. In other words, each of the connectors  35 A and  35 B stationarily fixes a corresponding one of the ends of the electrically conductive plate  31  in the width direction to the holder  33 . 
     Each of the connectors  35 A and  35 B is made of a thermoplastic resin. The thermoplastic resin that constitutes each of the connectors  35 A and  35 B has thermal resistance and electric insulation properties, and has properties of low thermal conductivity (a low thermal conductivity rate). For this reason, each of the connectors  35 A and  35 B has lower heat thermal conductivity than that of the electrically conductive plate  31 . Examples of the thermoplastic resin constituting each of the connectors  35 A and  35 B are: liquid crystal polymer (LCP), polyetheretherketone (PEEK), perfluoroalkoxy alkane (PFA), polytetrafluoroethylene (PTFE), polyimide (PI), and polybenzimidazole (PBI), and the like. The resin constituting the coating  52  of the holder  33  may have the same composition as the resin constituting the connectors  35 A and  35 B, or a composition differing from the resin constituting the connectors  35 A and  35 B. However, it is preferable that the coating  52  of the holder  33  be made of a resin having the same composition as the resin constituting the connectors  35 A and  35 B. 
     In the present embodiment, each of the connectors  35 A and  35 B is a member separate from the coating  52  of the holder  33 . For this reason, in the jaw  16 , an interface X 1  is formed between the connector  35 A and the coating  52 , and an interface X 2  is formed between the connector  35 B and the coating  52 . Each of the interfaces X 1  and X 2  continuously extends from the proximal portion to the distal portion of the jaw  16 , in the direction along the longitudinal axis C′ (the longitudinal direction of the end effector  8 ). 
     The thermoplastic resin constituting the connectors  35 A and  35 B has a melting point higher than a temperature of the treating surface  41  when treatment energy, such as the heat generated at the heater  32  or a high-frequency current, is applied to the treatment target. Herein, in a state where the treatment target is undergoing dissection using the heat generated in the heater  32 , the temperatures of the heater  32  and the treating surface  41  are, for example, around 300° C. For this reason, in the treatment instrument  2  that conducts dissection (cutting) of the treatment target using the heat generated by the heater  32 , the connectors  35 A and  35 B are made of a thermoplastic resin that has a melting point higher than 300° C. and that does not become softened to a deformable extent at the temperature of 300° C. and the vicinity thereof. From this point of view, in the treatment instrument  2  that conducts dissection of the treatment target using the heat generated by the heater  32 , LCP or PEEK, for example, is selected as a thermoplastic resin for constituting the connectors  35 A and  35 B. The resin that constitutes the coating  52  of the holder  33  also has a melting point higher than the temperature of the treating surface  41  when treatment energy is applied to the treatment target. For this reason, the resin that forms the coating  52  does not become softened to a deformable extent at the temperature of 300° C. or the vicinity thereof. 
     In the electrically conductive plate  31 , an engagement claw  61 A is provided in one end according to the width direction, and an engagement claw  61 B is provided in the other end according to the width direction. The engagement claw  61 A is arranged on the opposite side of the engagement claw  61 B with respect to the longitudinal axis C′ in the width direction. Each of the engagement claws  61 A and  61 B is formed continuously over the entire or substantially entire length of the electrically conductive plate  31  in the direction along the longitudinal axis C′, and projects toward the side on which the jaw  16  opens in the electrically conductive plate  31 . An engagement groove  62 A which the engagement claw  61 A engages is formed in the connector  35 A, and an engagement groove  62 B which the engagement claw  61 B engages is formed in the connector  35 B. Each of the engagement grooves  62 A and  62 B continuously extends from the proximal portion to the distal portion of the jaw  16 , in the direction along the longitudinal axis C′. In the connector  35 A, the engagement groove  62 A is recessed toward the side on which the jaw  16  opens, and in the connector  35 B, the engagement groove  62 B is recessed toward the side on which the jaw  16  opens. 
     In the cross section perpendicular or substantially perpendicular to the longitudinal axis C′ (the cross section intersecting with the longitudinal axis C′), the cross-sectional shape of each of the engagement grooves  62 A and  62 B is the same as the cross-sectional shape of a corresponding one of the engagement claws  61 A and  61 B. For this reason, in the engagement groove  62 A, a pressing pressure, etc. applied to the engagement claw  61 A from the connector  35 A can prevent an escape of the engagement claw  61 A from the engagement groove  62 A, and a release of the engagement between the engagement claw  61 A and the engagement groove  62 A. Similarly, in the engagement groove  62 B, a pressing pressure, etc. applied to the engagement claw  61 B from the connector  35 B can prevent an escape of the engagement claw  61 B from the engagement groove  62 B, and a release of the engagement between the engagement claw  61 B and the engagement groove  62 B. Accordingly, in the present embodiment, one end of the electrically conductive plate  31  in the width direction is firmly fixed to the holder  33  by the engagement between the engagement claw  61 A and the engagement groove  62 A, and the other end of the electrically conductive plate  31  in the width direction is firmly fixed to the holder  33  by the engagement between the engagement claw  61 B and the engagement groove  62 B. 
     The projection end and the vicinity thereof in each of the engagement claws  61 A and  61 B forms an anchor shape (either one of  63 A or  63 B) that becomes acute (radical) toward the outward side in the width direction in the cross section perpendicular or substantially perpendicular to the longitudinal axis C′. Furthermore, in the cross section perpendicular or substantially perpendicular to the longitudinal axis C′, the cross-sectional shape of the bottom and its vicinity of each of the engagement grooves  62 A and  62 B is the same anchor shape (either one of  65 A or  65 B) as the anchor shape (either one of  63 A or  63 B) of the engagement claw (either one of  61 A or  61 B) that engages the groove. For this reason, an escape of the engagement claw (either one of  61 A or  61 B) from the corresponding engagement groove (either one of  62 A or  62 B) can be effectively prevented, and a coupling strength of a corresponding connector (either one of  35 A or  35 B) of the engagement claw  61 A or  61 B can be improved. The electrically conductive plate  31  is thereby firmly coupled to the holder  33 . 
     In one example, each of the engagement claws  61 A and  61 B is formed discontinuously in the direction along the longitudinal axis C′. In this case, each of the engagement grooves  62 A and  62 B is formed discontinuously in the direction along the longitudinal axis C′ in correspondence to the engagement claws  61 A and  61 B. Furthermore, the corresponding one of the engagement claws  61 A and  61 B engages each of the engagement grooves  62 A and  62 B. 
     Next, a method of manufacturing the treatment instrument  2 , particularly a method of manufacturing the jaw  16  in which the heater  32  is provided as an electric component, will be described. When the jaw  16  is formed, the electrically conductive plate  31  including the treating surface  41 , the back surface  46 , and the engagement claws  61 A and  61 B, is made from a material having electrical conductivity such as a metal. Furthermore, the heater  32  which is an electric component is arranged on the back surface  46  of the electrically conductive plate  31 , and stationarily fixed to the electrically conductive plate  31 . At this time, the heater  32  is arranged in a manner such that the heater  32  is electrically independent from the electrically conductive plate  31 , through provision of an electrically insulating layer, etc. between the back surface  46  of the electrically conductive plate  31  and the heater  32 . In the manufacturing of the jaw  16 , the holder  33  is formed. When the holder  33  is formed, the coating  52  is formed by insert molding (injection molding) of a resin into the core member  51 , for example. Then, the electrically conductive plate  31  in which the heater  32  is stationarily fixed to the back surface  46  is supported by the holder  33  from the back surface  46  side. At this time, the supporting projection  53  of the holder  33  is abutted to the back surface  46  of the electrically conductive plate  31 , and the heater  32  fits into the mating concave portion  55  of the holder  33 . Then, the heater  32  is arranged between the electrically conductive plate  31  and the holder  33 . 
       FIG. 4  shows the process of forming the connectors  35 A and  35 B. As shown in  FIG. 4 , the connectors  35 A and  35 B are formed using a pair of dies  101  and  102  capable of opening and closing with respect to each other. Herein, one die  101  is a fixed type and the other die  102  is a movable type, as an example. If the dies  101  and  102  are closed to each other, a cavity  103  is generated between the dies  101  and  102 . When the connectors  35 A and  35 B are formed, the electrically conductive plate  31 , the heater  32 , and the holder  33  are stationarily fixed to the die  101 , with the dies  101  and  102  being open to each other. At this time, with the electrically conductive plate  31  being supported by the holder  33  from the back surface  46  side, the electrically conductive plate  31 , the heater  32 , and the holder  33  are arranged. 
     Then, the dies  101  and  102  are closed to each other, and the electrically conductive plate  31 , the heater  32 , and the holder  33  are arranged in the cavity  103  thereby formed. At this time, in the cavity  103 , a space is formed in each area on both sides of the supporting projection  53  of the holder  33  in the width direction of the jaw  16 . In the space formed in the cavity  103 , the engagement claw  61 A is arranged on one side relative to the holder  33  in the width direction, and the engagement claw  61 B is arranged on the other side relative to the holder  33  in the width direction. In the cavity  103 , a heated and softened thermoplastic resin is injected into the space on both sides relative to the supporting projection  53  in the width direction. In other words, the thermoplastic resin is injected into a region distant from the heater  32  in the width direction. Then, the injected thermoplastic resin is cooled and hardened. At this time, the thermoplastic resin is naturally cooled, for example. Thus, the thermoplastic resin forms into the connectors  35 A and  35 B on both sides of the supporting projection  53  in the width direction. In other words, the connectors  35 A and  35 B are formed using the thermoplastic resin by insert molding at a region distant from the heater  32  in the width direction. 
     Through the formation of the connector  35 A, one end of the electrically conductive plate  31  in the width direction is stationarily fixed to the holder  33 . And through the formation of the connector  35 B, the other end of the electrically conductive plate  31  in the width direction is stationarily fixed to the holder  33 . The interface X 1  is formed between the connector  35 A and the holder  33  by forming the connector  35 A, and the interface X 2  is formed between the connector  35 B and the holder  33  by forming the connector  35 B. 
     Herein, in a state where the treatment target is undergoing dissection by the heat generated in the heater  32 , the temperature of the heater  32  and its vicinity is around 300° C. For this reason, if the temperature of the heater  32  and its vicinity is around 300° C. or lower than 300° C., the heater  32  works properly. However, if the temperature of the heater  32  and its vicinity rises to around 350° C., the influence of the heat on the heater  32  becomes significant, and the heater  32  may not work properly. 
     To this end, the temperature of the heater  32  and its vicinity was measured and verification was conducted for the case of insert molding of the connectors  35 A and  35 B in a manner similar to the present embodiment. In the verification, the temperature of the heater  32  and its vicinity was measured for the case where the connectors  35 A and  35 B are formed by insert molding using PEEK as a material. The temperature of the dies  101  and  102  was set at 200° C., and either one of PEEK or LCP at 400° C. was injected. When the connectors  35 A and  35 B were formed by insert molding under this condition in a manner similar to the present embodiment, the temperature of the heater  32  and its vicinity was kept lower than 250° C. during the insert molding of the connectors  35 A and  35 B. 
     As described above, in each case of the verification, when the connectors  35 A and  35 B were formed in a manner similar to the present embodiment, the increase in the temperature of the heater  32  and its vicinity up to around 350° C. was prevented in the insert molding of the connectors  35 A and  35 B. Accordingly, it was proved that the heater  32  was influenced almost not at all by the heat from the injected thermoplastic resin at the time of manufacture. 
     As described above, in the present embodiment, the heated thermoplastic resin is injected into the region distant from the heater  32  in the width direction during the insert molding. Furthermore, between the injected resin and the heater  32  there is the coating  52  of the holder  33  having a low thermal conductivity, in addition to the electrically conductive plate  31 . For this reason, the heat from the injected resin is transferred to the heater  32  mainly through the electrically conductive plate  31 , but is not easily transferred to the heater  32  through the coating  52  of the holder  33 . Thus, in the insert molding of the connectors  35 A and  35 B, in other words, at the time of manufacture, the influence of the heat of the injected thermoplastic resin onto the heater  32  can be reduced. Through the reduction of the thermal influence on the heater  32  at the time of manufacture, the heater  32  works properly when it is used after manufacturing, and the heat generated in the heater  32  is used to perform a treatment appropriately. 
     In the present embodiment, the resin that constitutes the connectors  35 A and  35 B and the coating  52  of the holder  33  also has a melting point higher than the temperature of the treating surface  41  when treatment energy is applied to the treatment target. Then, under the state in which a treatment target undergoes dissection using the heat generated by the heater  32 , namely the state in which the treating surface  41  has the temperature of around 300° C., the connectors  35 A and  35 B and the coating  52  do not become softened to a deformable extent. For this reason, in a treatment, such as a dissection of a treatment target using heat generated by the heater  32 , for example, the deformation of the connectors  35 A and  35 B and the holder  33  can be prevented. It is thereby possible to effectively prevent the electrically conductive plate  31  from being detached from the connectors  35 A and  35 B and the holder  33 . 
     Modifications of First Embodiment 
     In a first modification of the first embodiment shown in  FIGS. 5 and 6 , a core (for example,  51 ) is not provided in the holder  33 , and the entire holder  33  is made from a resin. In this case, a material of the holder  33  may be a resin having a same composition as a resin constituting the coating  52  in the first embodiment, for example. The holder  33  is formed by injection molding of a resin. In the present modification, the entire holder  33  may be made from ceramics, instead of such a resin. In either case, the holder  33  is made of a material having thermal resistance and electric insulation properties, and properties of low thermal conductivity (a low thermal conductivity rate). Furthermore, the holder  33  has a lower thermal conductivity than that of the electrically conductive plate  31 . In the present modification, the holder  33  supports the electrically conductive plate  31  from the back surface  46  side, and the heater  32  is arranged between the electrically conductive plate  31  and the holder  33 . 
     In the present modification, a base  70  is provided in the jaw  16 , and the base  70  supports the holder  33  from the side on which the jaw  16  opens. The base  70  continuously extends from the proximal portion to the distal portion of the jaw  16  in the direction along the longitudinal axis C′ (the longitudinal direction of the end effector  8 ). The base  70  includes a core member  71  made of a metal, etc., and a coating  72  that coats the core member  71 . Each of the core member  71  and the coating  72  continuously extends from the proximal portion to the distal portion of the jaw  16  (base  70 ) in the direction along the longitudinal axis C′. In the present modification, the core member  71  is abutted to the holder  33  from the side on which the jaw  16  opens. The coating  72  is formed at portions on both sides of the holder  33  in the width direction of the jaw  16 , portions on both sides of the core member  71  in the width direction of the jaw  16 , and a portion on the side on which the jaw  16  opens with respect to the core member  71 . 
     In the present modification, a part of the coating  72  constitutes the connectors  35 A and  35 B, and the holder  33  is arranged between the connectors  35 A and  35 B in the width direction. Even in the present modification, the connector  35 A is provided on the opposite side of the connector  35 B with respect to the longitudinal axis C′ in the width direction. Each of the connectors  35 A and  35 B is arranged at a distance from the heater  32  toward an outer side in the width direction of the end effector  8 , and is stationarily fixed to the holder  33 . Furthermore, each of the connectors  35 A and  35 B stationarily fixes a corresponding one of the ends of the electrically conductive plate  31  in the width direction to the holder  33 . Even in the present embodiment, an interface X 1  is formed between the connector  35 A and the holder  33 , and an interface X 2  is formed between the connector  35 B and the holder  33 . 
     The coating  72  is formed by insert molding (injection molding) wherein a resin is inserted to encapsulate the core member  71  and the holder  33 , for example. As a material constituting the coating  72  including the connectors  35 A and  35 B, a thermoplastic resin having the same composition as the thermoplastic resin constituting the connectors  35 A and  35 B in the first embodiment is used for example, and it may be LCP or PEEK, etc. The coating  72  including the connectors  35 A and  35 B is made of a material having thermal resistance, electric insulation properties, and low thermal conductivity (a low thermal conductivity). Furthermore, the coating  72  has a lower thermal conductivity than that of the electrically conductive plate  31 . The thermoplastic resin constituting the coating  72  (the connectors  35 A and  35 B) has a melting point higher than a temperature of the treating surface  41  when treatment energy, such as the heat generated at the heater  32  or a high-frequency current, is applied to the treatment target. 
       FIG. 6  shows the process of forming the connectors  35 A and  35 B in the present modification. As shown in  FIG. 6 , even in the present modification, the connectors  35 A and  35 B are formed using a pair of dies  101  and  102 . In the present modification, the die  102  is a fixed type, and the die  101  is a movable type. When the connectors  35 A and  35 B are formed, the electrically conductive plate  31 , the heater  32 , the holder  33 , and the core member  71  are stationarily fixed to the die  102 , with the dies  101  and  102  being open to each other. At this time, with the electrically conductive plate  31  being supported by the holder  33  from the back surface  46  side, and with the core member  71  supporting the holder  33  from the side on which the jaw  16  opens, the electrically conductive plate  31 , the heater  32 , the holder  33 , and the core member  71  are arranged. 
     Then, the dies  101  and  102  are closed to each other, and the electrically conductive plate  31 , the heater  32 , the holder  33 , and the core member  71  are arranged in the cavity  103  thereby formed. At this time, in the cavity  103 , a space is formed in the areas on both sides of the holder  33  and the core member  71  in the width direction of the jaw  16 , and in the area on the side on which the jaw  16  opens with respect to the core member  71 . In the space formed in the cavity  103 , the engagement claw  61 A is arranged on one side relative to the holder  33  in the width direction, and the engagement claw  61 B is arranged on the other side relative to the holder  33  in the width direction. In the cavity  103 , a heated and softened thermoplastic resin is injected into the space. At this time, the thermoplastic resin is injected into a region distant from the heater  32  according to the width direction. Then, the injected thermoplastic resin is cooled and hardened. Thus, the coating  72  is formed, and the thermoplastic resin forms into the connectors  35 A and  35 B on both sides of the holder  33  in the width direction. In other words, the connectors  35 A and  35 B are formed using the thermoplastic resin by insert molding at a region distant from the heater  32  in the width direction. 
     In the present modification, the heated thermoplastic resin is injected into the region distant from the heater in the width direction during the insert molding. Furthermore, in addition to the electrically conductive plate  31 , there is the holder  33  having low thermal conductivity between the injected resin and the heater  32 . For this reason, the heat from the injected resin is transferred to the heater  32  mainly through the electrically conductive plate  31 , but is not easily transferred to the heater  32  through the holder  33 . Thus, in the present modification, similarly to the first embodiment, in the insert molding of the connectors  35 A and  35 B, in other words, at the time of manufacture, the influence of the heat of the injected thermoplastic resin onto the heater  32  can be reduced. 
     In a second modification of the first embodiment shown in  FIG. 7 , similarly to the first modification, the base  70  is provided, and the coating  72  of the base  70  constitutes the connectors  35 A and  35 B. In the present modification, a space  75  is formed between the holder  33  and the core member  71  of the base  70 . Since the space  75  is formed, transfer of the heat of the heater  32  and the Joule heat caused by a high-frequency current to the back surface  42  of the jaw  16  becomes more difficult. 
     In a third modification of the first embodiment shown in  FIGS. 8 and 9 , instead of forming the anchor shape ( 63 A and  63 B) in the engagement claws  61 A and  61 B, through-holes  76 A and  76 B are formed in the engagement claws  61 A and  61 B, respectively. Each of the through-holes  76 A and  76 B passes through the corresponding engagement claw (either one of  61 A and  61 B) in the width direction of the jaw  16 . Each of the through-holes  76 A and  76 B may extend continuously from the proximal portion to the distal portion of the jaw  16 , in the direction along the longitudinal axis C′, or may be formed discontinuously in the direction along the longitudinal axis C′. In the present modification, a filling (either  77 A or  77 B) to be filled into a corresponding through-hole (either one of  76 A or  76 B) is formed in each of the connectors  35 A and  35 B. 
     In the present modification, in the insert molding of the connectors  35 A and  35 B, the injected thermoplastic resin is filled into the through-holes  76 A and  76 B. Fillings  77 A and  77 B are thereby formed in the connectors  35 A and  35 B, respectively. In the present modification, a coupling strength between the engagement claw  61 A or  61 B and its corresponding connector (either  35 A or  35 B) can be improved by the through-holes  76 A and  76 B and the fillings  77 A and  77 B. The electrically conductive plate  31  is thereby firmly coupled to the holder  33 . 
     In a fourth modification of the first embodiment shown in  FIGS. 10 and 11 , a block  80  is provided in the proximal portion of the jaw  16 , and the block  80  is connected to the proximal side of the electrically conductive plate  31 . The block  80  has electric insulation properties and is made of a material having properties of low thermal conductivity (a low thermal conductivity rate), such as a resin. In the block  80 , the surface facing the side on which the jaw  16  closes is formed in parallel or substantially parallel to the width direction of the end effector  8 . In the block  80 , the projecting portion  81  projecting toward the side on which the jaw  16  closes is formed. 
     In the jaw  16 , a circuit system  82  including a heater line of the heater  32  is provided. In the inside of the shaft  6 , electric wiring  83  for supplying electric energy to the heater  32  extends. In the proximal portion of the jaw  16 , a connecting portion of the circuit system  82  to the electric wiring  83  is formed. The block  80  serves as a cover that prevents exposure of the proximal portion of the circuit system  82  and the connecting portion of the electric wiring  83  to the circuit system  82 . In a state in which a treatment target is grasped between the jaws  15  and  16 , the projecting portion  81  of the block  80  prevents the invasion of the treatment target into the proximal side from the projecting portion  81 . It is thereby possible to effectively prevent the invasion of the grasped treatment target into the inside of the shaft  6 . 
     In the present modification, the holder  33  supports the electrically conductive plate  31  and the block  80  from the back surface  46  side of the electrically conductive plate  31 . Furthermore, each of the connectors  35 A and  35 B stationarily fixes a corresponding one of the ends of the electrically conductive plate  31  in the width direction to the holder  33 , and a corresponding one of the ends of the block  80  in the width direction to the holder  33 . 
     In the present modification, in the insert molding of the connectors  35 A and  35 B, the thermoplastic resin is injected under a state in which the holder  33  supports the electrically conductive plate  31  and the block  80 . Then, the injected resin is formed into the connectors  35 A and  35 B, and the electrically conductive plate  31  and the block  80  are attached to the holder  33  via the connectors  35 A and  35 B. 
     As in the fifth modification of the first embodiment shown in  FIG. 12 , a projecting portion (for example,  81 ) is not necessarily provided in the block  80 . Even in this case, the block  80  prevents exposure of the proximal portion of the circuit system  82  and the connecting portion of the electric wiring  83  to the circuit system  82 . 
     Second Embodiment 
     Next, the second embodiment will be explained with reference to  FIGS. 13 and 14 . The second embodiment is a modification of the processing in the first embodiment, as will be described below. Herein, the same elements as those in the first embodiment are specified by the same reference numbers, and a duplicate description of such elements will be omitted. 
     As shown in  FIG. 13 , in the present embodiment, a part of the coating  52  of the holder  33  constitutes the connectors  35 A and  35 B. Also in the present embodiment, the connector  35 A is provided on the opposite side of the connector  35 B with respect to the longitudinal axis C′ in the width direction. Each of the connectors  35 A and  35 B is arranged at a distance from the heater  32  in the width direction of the end effector  8 . Furthermore, each of the connectors  35 A and  35 B stationarily fixes a corresponding one of the ends of the electrically conductive plate  31  in the width direction to the holder  33 . In the present embodiment, however, the interfaces X 1  and X 2  are not formed because the connectors  35 A and  35 B are integrated with the holder  33 . 
     Similarly to the first embodiment, the coating  52  of the present embodiment is also formed by insert molding (injection molding) of a resin into the core member  51 . As a material constituting the coating  52  including the connectors  35 A and  35 B, a thermoplastic resin having the same composition as the thermoplastic resin constituting the connectors  35 A and  35 B in the first embodiment is used for example, and it may be LCP or PEEK, etc. Similarly to the first embodiment, the coating  52  including the connectors  35 A and  35 B of the present embodiment is also made of a material having thermal resistance and electric insulation properties, and properties of low thermal conductivity (a low thermal conductivity rate). Furthermore, the coating  52  has a lower thermal conductivity than that of the electrically conductive plate  31 . The thermoplastic resin constituting the coating  52  (the connectors  35 A and  35 B) has a melting point higher than a temperature of the treating surface  41  when treatment energy, such as the heat generated at the heater  32  or a high-frequency current, is applied to the treatment target. 
     Similarly to the first embodiment, the coating  52  of the present embodiment includes the supporting projection  53  projecting toward the side on which the jaw  16  closes. In the present embodiment, in addition to the supporting projection  53 , the coating  52  includes projections  91 A and  91 B projecting toward the side on which the jaw  16  closes. The projection  91 A is arranged on one side relative to the supporting projection  53  in the width direction of the jaw  16 , and the projection  91 B is arranged on the other side relative to the supporting projection  53  in the width direction of the jaw  16 . Each of the projections  91 A and  91 B is continuously formed from the proximal portion toward the distal portion of the jaw  16 . Each of the projections  91 A and  91 B is arranged at a distance from the heater  32  according to the width direction of the end effector  8 . 
     In the present embodiment, the engagement groove  62 A is formed between the supporting projection  53  and the projection  91 A in the width direction of the jaw  16 . Then, the engagement claw  61 A of the electrically conductive plate  31  engages the engagement groove  62 A. Thus, in the coating  52 , the engagement groove  62 A and its vicinity constitute the connector  35 A. Similarly, in the present embodiment, the engagement groove  62 B is formed between the supporting projection  53  and the projection  91 B in the width direction of the jaw  16 . Then, the engagement claw  61 B of the electrically conductive plate  31  engages the engagement groove  62 B. Thus, in the coating  52 , the engagement groove  62 B and its vicinity constitute the connector  35 B. 
       FIG. 14  shows the process of forming the connectors  35 A and  35 B in the present embodiment. In the present embodiment, similarly to the first embodiment, the coating  52  of the holder  33  is formed by the insert molding of the core member  51 . However, as shown in  FIG. 14 , in the coating  52  formed by the insert molding, a concave portion  93 A is formed between the supporting projection  53  and the projection  91 A in the width direction. Similarly, in the coating  52  formed by the insert molding, the concave portion  93 B is formed between the supporting projection  53  and the projection  91 B in the width direction. At this time, each of the concave portions  93 A and  93 B continuously extends from the proximal portion to the distal portion of the holder  33 . 
     Then, the electrically conductive plate  31  is supported by the holder  33  from the back surface  46  side. In one example, the engagement claws  61 A and  61 B of the electrically conductive plate  31  are moved along the longitudinal direction with respect to the holder  33 , so as to be arranged at desirable positions. In another example, the engagement claws  61 A and  61 B of the electrically conductive plate  31  are arranged at desirable positions with respect to the holder  33  from the direction perpendicular to the longitudinal direction and the width direction. Thus, the supporting projection  53  of the holder  33  is abutted to the back surface  46  of the electrically conductive plate  31 . Furthermore, the engagement claw  61 A of the electrically conductive plate  31  is inserted into the concave portion  93 A, and the engagement claw  61 B of the electrically conductive plate  31  is inserted into the concave portion  93 B. Herein, in the cross section perpendicular or substantially perpendicular to the longitudinal axis C′ (the cross section intersecting with the longitudinal axis C′), the cross-sectional shape of each of the concave portions  93 A and  93 B is different from the cross-sectional shape of a corresponding one of the engagement claws  61 A and  61 B. For this reason, each of the engagement claws  61 A and  61 B can escape from the concave portion (either one of  93 A or  93 B). 
     In the present embodiment, the connectors  35 A and  35 B are formed using a heated horn  105 . At this time, in a state in which the holder  33  supports the electrically conductive plate  31  and the engagement claws  61 A and  61 B are inserted into the concave portions  93 A and  93 B respectively, the heated horn  105  is brought into contact with the projections  91 A and  91 B of the coating  52 . The heat is thereby supplied to the projections  91 A and  91 B of the coating  52 . In other words, the heat is supplied to the coating  52  of the holder  33  at a region distant from the heater  32  in the width direction. Through the supply of the heat, the projections  91 A and  91 B made of the thermoplastic resin become softened and deformed. Then, the deformed projections  91 A and  91 B are cooled and hardened. Thus, the connectors  35 A and  35 B are formed on both sides of the holder  33  in the width direction. In other words, a part of the holder  33  (the projections  91 A and  91 B) is thermally caulked or swaged, thereby forming the connectors  35 A and  35 B in the holder  33 . 
     Through the deformation of the projections  91 A and  91 B by the thermal caulking, the cross-sectional shape of each of the concave portions  93 A and  93 B in the cross section perpendicular to or substantially perpendicular to the longitudinal axis C′ is deformed in the holder  33 . The thermal caulking causes the change in the cross-sectional shape of each of the concave portions  93 A and  93 B, and in turn in the holder  33 , and the change leads into the formation of the engagement groove  62 A between the supporting projection  53  and the projection  91 A in the width direction, and the formation of the engagement groove  62 B between the supporting projection  53  and the projection  91 B in the width direction. Through the formation of the engagement grooves  62 A and  62 B, the escape of the engagement claws  61 A and  61 B from respective engagement grooves  62 A and  62 B can be prevented. 
     Herein, the temperature of the heater  32  and its vicinity was measured and verification was conducted for the case of forming the connectors  35 A and  35 B by the thermal caulking in a manner similar to the present embodiment. In the verification, the temperature of the heater  32  and its vicinity was measured for the case where the coating  52  (the connectors  35 A and  35 B) of the holder  33  is made of PEEK. At this time, the temperature of the horn  105  was set to 350° C., and heat was supplied to the projections  91 A and  91 B of the holder  33 . When the connectors  35 A and  35 B were formed under this condition in a manner similar to the present embodiment, the temperature of the heater  32  and its vicinity was kept lower than 300° C. during the thermal caulking of the projections  91 A and  91 B. In another verification, the temperature of the heater  32  and its vicinity was measured for the case where the coating  52  (the connectors  35 A and  35 B) of the holder  33  is made of LCP. At this time, the temperature of the horn  105  was set to 370° C., and heat was supplied to the projections  91 A and  91 B of the holder  33 . When the connectors  35 A and  35 B were formed under this condition in a manner similar to the present embodiment, the temperature of the heater  32  and its vicinity was kept lower than 300° C. during the thermal caulking of the projections  91 A and  91 B. 
     As described above, in each case of the verification, when the connectors  35 A and  35 B are formed by thermal caulking in a manner similar to the present embodiment, the increase of the temperature of the heater  32  and its vicinity up to around 350° C. was prevented in the thermal caulking. Accordingly, it was proved that the heater  32  was influenced almost not at all by the heat supplied to the holder  33  at the time of manufacture. 
     As described above, in the present embodiment, the heat is supplied to the holder  33  in a region distant from the heater  32  according to the width direction when the connectors  35 A and  35 B are formed. Furthermore, in addition to the electrically conductive plate  31 , there is the coating  52  of the holder  33  having a low thermal conductivity between the portion to which the heat is applied in the holder  33  and the heater  32 . For this reason, the heat applied from the horn  105  is transferred to the heater  32  mainly through the electrically conductive plate  31 , and is not easily transferred to the heater  32  through the coating  52  of the holder  33 . Thus, in the formation of the connectors  35 A and  35 B, in other words, at the time of manufacture, the influence of the heat supplied to the holder  33  onto the heater  32  can be reduced. In other words, even in the present embodiment, similarly to the first embodiment, the thermal influence on the heater  32  at the time of manufacture can be reduced. Accordingly, also in the present embodiment, the heater  32  works properly when it is used after manufacturing, and the heat generated in the heater  32  is used to perform a treatment appropriately. 
     In the present embodiment, the resin that constitutes the coating  52  of the holder  33  including the connectors  35 A and  35 B also has a melting point higher than the temperature of the treating surface  41  when treatment energy is applied to the treatment target. Then, under the state in which a treatment target undergoes dissection using the heat generated by the heater  32 , namely the state in which the treating surface  41  has a temperature of 300° C. or so, the coating  52  including the connectors  35 A and  35 B does not become softened to a deformable extent. For this reason, similarly to the first embodiment, the deformation of the connectors  35 A and  35 B and the holder  33  can be prevented in the present embodiment during a treatment, such as a dissection of a treatment target using heat generated by the heater  32 , for example. 
     Modifications of Second Embodiment 
     In a modification of the second embodiment shown in  FIG. 15 , the through-holes  76 A and  76 B are respectively formed in the engagement claws  61 A and  61 B, similarly to the modification of the first embodiment shown in  FIGS. 8 and 9 . Even in the present modification, similarly to the second embodiment, the projections  91 A and  91 B are provided in the holder  33 , as well as the connectors  35 A and  35 B in the holder  33 . In the present modification, the inserted portions  95 A and  95 B, which are respectively inserted into the through-holes  76 A and  76 B, are respectively formed in the projections  91 A and  91 B. Each of the inserted portions  95 A and  95 B is inserted into a corresponding through-hole (either one of the through-holes  76 A and  76 B) from an outer side in the width direction of the jaw  16 . 
     In the present modification, heat is supplied to the projections  91 A and  91 B of the holder  33  from a heated horn  106  so as to soften and deform the projections  91 A and  91 B, and the projections  91 A and  91 B are inserted into the through-holes  76 A and  76 B, respectively. In other words, the projections  91 A and  91 B are respectively inserted into the through-holes  76 A and  76 B by thermal caulking. Thus, the inserted portions  95 A and  95 B are respectively formed in the projections  91 A and  91 B of the holder  33 . In the present modification, the through-holes  76 A and  76 B and the inserted portions  75 A and  75 B improve the coupling strength between the engagement claw  61 A ( 61 B) and the connector  35 A ( 35 B). The electrically conductive plate  31  is thereby more firmly coupled to the holder  33 . 
     In another modification, the holder  33  is abutted only to the back surface  46  of the electrically conductive plate  31 , and not to the heater  32 . In this case, a space is formed between the holder  33  and the heater  32  in such a manner that the space is formed adjacently to the heater  32  on the side on which the jaw  16  opens. 
     In another modification, in a configuration wherein the connectors  35 A and  35 B are formed integrally with the holder  33 , the block  80  is provided, similarly to the modification of the first embodiment shown in  FIGS. 10 and 11 . In this case, a part of the holder  33  is softened and deformed by thermal caulking, and the connectors  35 A and  35 B are thereby formed, and the electrically conductive plate  31  and the block  80  are attached to the holder  33  via the connectors  35 A and  35 B. 
     Other Modifications 
     In the foregoing embodiments, the heater  32  is provided as an electric component; however, in a modification, for example, a sensor that detects a temperature of the end effector  8  or a sensor that detects a position or a posture of the end effector  8  may be provided as an electric component. Also in this case, the sensor is electrically insulated from the electrically conductive plate  31  and electrically independent from the electrically conductive plate  31 . In the present modification, electric energy is supplied to the electrically conductive plates  22  and  31  based on an operation at the operation apparatus  10 . When electric energy is supplied to the electrically conductive plates  22  and  31 , a high-frequency current flows between the electrically conductive plates  22  and  31  via the grasped treatment target, and the high-frequency current is thereby applied to the treatment target. At this time, the temperature of the treating surface  41  is between around 120° C. and 130° C. due to Joule heat caused by the high-frequency current. For this reason, in the present modification in which a sensor is provided instead of the heater  32  as an electric component, the connectors  35 A and  35 B are made of a thermoplastic resin that has a melting point higher than 130° C. and that does not get softened to a deformable extent at the temperature of 130° C. and the vicinity thereof. 
     In one modification, in a configuration with the electrically conductive plate  31  and electric components such as the heater  32  and the sensor, etc. electrically independent from the electrically conductive plate  31 , similarly to the foregoing embodiments, a cutter that can move on the treating surface  41  of the electrically conductive plate  31  may be provided. In this case, the cutter is movable on the treating surface  41  along the longitudinal axis of the end effector  8 . While a treatment target is being grasped between the jaws  15  and  16 , the grasped treatment target undergoes dissection when the cutter is moved on the treating surface. In the foregoing embodiments, etc., the end effector  8  has a pair of jaws  15  and  16 ; however, in a modification, a counter electrode plate disposed in a subject (e.g., human body) is provided, instead of the jaw  15 . In this case, electric energy is supplied to the electrically conductive plate  31  and the counter electrode plate based on an operation at the operation apparatus  10 . Furthermore, when electric energy is supplied to the electrically conductive plate  31  and the counter electrode plate in a state in which the treating surface  41  of the electrically conductive plate  31  is in contact with the treatment target, a high-frequency current flows through the treatment target, and the high-frequency current is thereby supplied to the treatment target. In other words, the foregoing configuration is applicable not only to a treatment instrument that performs a bipolar treatment in which a high-frequency current flows between a pair of jaws, but also to a treatment instrument that performs monopolar treatment in which a high-frequency current flows between a counter electrode plate and an end effector. 
     Additional advantages and modifications will readily occur to those skilled in the art. Therefore, the exemplary embodiments in broader aspects is not limited to the specific details and representative embodiments shown and described herein. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents.