Abstract:
A surgical operating apparatus includes rod-shaped probe main body which is inserted into a sheath and has a distal end and which is configured to transmit ultrasonic vibration, a jaw pivoted to a distal end of the sheath, a probe distal end which is provided at the distal end of the probe main body and a driving member including a tubular main body portion configured to be inserted into the sheath slidably along an axial direction of the sheath and an acting portion which is provided at a distal end of the main body portion and has a connection portion connected to the jaw, the connection portion positioned. The sheath includes a notched portion positioned and configured to prevent the sheath from contacting the proximal portion of the jaw.

Description:
CROSS-REFERENCE TO RELATED APLICATIONS 
     This application is a continuation-in-part of U.S. patent application Ser. No. 11/862,562, filed on Sep. 27, 2007, abandoned. 
    
    
     BACKGROUND OF THE INVENTION 
     The present invention relates to a surgical operating apparatus which performs therapeutic treatment, such as incision, resection or coagulation, of a living body tissue by making use of composite energy of ultrasonic and high-frequency waves, and which can also perform therapeutic treatment by high-frequency waves. 
     Jpn. Pat. Appln. KOKAI Publication No. 2005-278932 (Patent Document 1), for instance, discloses an ultrasonic therapeutic apparatus as a general example of an ultrasonic therapeutic apparatus which can perform therapeutic treatment, such as incision, resection or coagulation, of a living body tissue by making use of ultrasonic and can also perform therapeutic treatment by high-frequency waves. 
     In this apparatus, a proximal-side operation section is coupled to a proximal end portion of an elongated insertion section. An ultrasonic transducer which generates ultrasonic vibration is provided in the operation section. A therapeutic section for treating a living body tissue is provided at a distal end portion of the insertion section. 
     The insertion section has an elongated tubular sheath. A rod-shaped vibration transmission member (probe) is inserted in the sheath. A proximal end portion of the vibration transmission member is detachably attached to the ultrasonic transducer via a screw-type coupling section. Ultrasonic vibration, which is generated by the ultrasonic transducer, is transmitted to a probe distal end portion at the distal end side of the vibration transmission member. 
     In the therapeutic section, a jaw is provided so as to be opposed to the probe distal end portion. A proximal end portion of the jaw is rotatably supported on a distal end portion of the sheath via a support shaft. A driving pipe for driving the jaw is inserted in the sheath so as to be axially advancible/retreatable. 
     A pin receiving section is formed at a distal end portion of the driving pipe. The pin receiving section is formed in an extension portion which is extended, as one body with the driving pipe, to a distal end side from a distal end edge portion of the driving pipe. A coupling pin is provided at a distal end portion of the pin receiving section. The driving pipe and the jaw body are coupled by the coupling pin. 
     The operation section is provided with an operation handle. In accordance with the operation of the operation handle, the driving pipe is axially advanced/retreated. In interlock with the operation of the driving pipe, the jaw is opened/closed relative to the probe distal end portion. 
     At this time, a living body tissue is held between the probe distal end portion and the jaw in accordance with the closing operation of the jaw. In this state, ultrasonic vibration from the ultrasonic transducer is transmitted to the probe distal end portion on the therapeutic section side via the vibration transmission member. Thereby, using ultrasonic, therapeutic treatment, such as incision, resection or coagulation, of the living body tissue is performed. 
     In addition, in the apparatus of the above-described Patent Document 1, a proximal end portion of the sheath is detachably coupled to the operation handle of the operation section. Further, a high-frequency connection pin is attached to the operation section. An electric cord for supplying high-frequency current from a high-frequency cauterization power supply device is connected to the high-frequency connection pin. An inner end portion of the high-frequency connection pin is electrically connected to the probe distal end portion of the therapeutic section or to the jaw via an electric conduction path within the operation section and the sheath. High-frequency current is supplied, when necessary, to the probe distal end portion of the therapeutic section or to the jaw, and high-frequency therapeutic treatment, such as coagulation, of the living body tissue is performed. 
     In the apparatus of the above-described Patent Document 1, when high-frequency therapeutic treatment is performed, the driving pipe is axially advanced/retreated in accordance with the operation of the operation handle, and the jaw is opened/closed relative to the probe distal end portion in interlock with the operation of the driving pipe. In addition, the pin receiving section is formed at the distal end portion of the driving pipe. The pin receiving section is formed in the extension portion which is extended, as one body with the driving pipe, to the distal end side from the distal end edge portion of the driving pipe. The coupling pin is provided at the distal end portion of the pin receiving section. The driving pipe and the jaw body are coupled by the coupling pin. 
     BRIEF SUMMARY OF THE INVENTION 
     A surgical operating apparatus in one aspect of the present invention comprises: a sheath having a distal end and a proximal end; a rod-shaped probe main body which is inserted into the sheath and has a distal end and a proximal end, and which is transmitted with ultrasonic vibration; a jaw pivoted to the distal end of the sheath; a probe distal end which is provided at the distal end of the probe main body and meshes with the jaw; and a driving member which is provided with a tubular main body portion which is inserted into the sheath slidably along an axial direction of the sheath and an acting portion which is provided at a distal end of the main body portion and has a connection portion connected to the jaw, for rotating the jaw according to a sliding action of the main body portion, wherein the sheath includes a notched portion for preventing the sheath from contacting the driving member when the connection portion of the driving member with the jaw moves in a direction perpendicular to a sliding direction of the driving member at a rotation time of the jaw. 
     Preferably, the notched portion is formed on a peripheral wall face of the distal end of the sheath corresponding to a moving direction of the jaw at the moving time of the jaw in an opening operation direction of the jaw. 
     Preferably, the sheath is covered with an outer skin formed from insulating material, and the notched portion is covered with the outer skin. 
     Preferably, the acting portion has a tapered shape portion which is gradually and gently narrowed toward a distal end of a tubular body of the main body portion, the tapered shape portion has a U-shaped extension portion with U shape in sectional configuration at the distal end of the tubular body of the main body portion, the U-shaped extension portion has two side faces disposed so as to be opposed to each other and a connected face connecting the two side faces, the connected face has an inclined face where a distance between the two side faces is gradually tapered toward a distal end of the connected face, and the connection portion is formed on each of the two side faces disposed at distal ends of the connected face. 
     Advantages of the invention 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 invention. Advantages of the invention 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 of the invention, and together with the general description given above and the detailed description of the embodiments given below, serve to explain the principles of the invention. 
         FIG. 1  is a perspective view that schematically shows the entire structure of an ultrasonic therapeutic apparatus according to a first embodiment of the present invention; 
         FIG. 2  is a perspective view showing a disassembled state of the ultrasonic therapeutic apparatus according to the first embodiment, with coupling sections of assembly units of the ultrasonic therapeutic apparatus being disconnected; 
         FIG. 3  is a side view showing a coupled state between a handle unit and a transducer unit of the ultrasonic therapeutic apparatus according to the first embodiment; 
         FIG. 4  is a longitudinal cross-sectional view showing an internal structure of the transducer unit of the ultrasonic therapeutic apparatus according to the first embodiment; 
         FIG. 5  is a plan view showing a probe unit of the ultrasonic therapeutic apparatus according to the first embodiment; 
         FIG. 6  is a cross-sectional view taken along line VI-VI in  FIG. 5 ; 
         FIG. 7  is a plan view showing a distal end portion of the probe unit of the ultrasonic therapeutic apparatus according to the first embodiment; 
         FIG. 8A  is a longitudinal cross-sectional view showing a distal end portion of a sheath unit of the ultrasonic therapeutic apparatus according to the first embodiment; 
         FIG. 8B  is a plan view showing a jaw of the sheath unit of the ultrasonic therapeutic apparatus according to the first embodiment; 
         FIG. 9A  is a longitudinal cross-sectional view showing a proximal end portion of the sheath unit of the ultrasonic therapeutic apparatus according to the first embodiment; 
         FIG. 9B  is a cross-sectional view taken along line IXB-IXB in  FIG. 9A ; 
         FIG. 10  is a side view showing an attachment section of the jaw of the ultrasonic therapeutic apparatus according to the first embodiment; 
         FIG. 11  is a perspective view showing a state in which the jaw of the ultrasonic therapeutic apparatus according to the first embodiment is opened; 
         FIG. 12  is a perspective view showing, in a direction different from the direction in  FIG. 11 , the state in which the jaw of the ultrasonic therapeutic apparatus according to the first embodiment is opened; 
         FIG. 13  is a perspective view showing a hold member of the jaw of the ultrasonic therapeutic apparatus according to the first embodiment; 
         FIG. 14  is a side view showing a jaw body of the jaw of the ultrasonic therapeutic apparatus according to the first embodiment; 
         FIG. 15  is a side view showing an electrode member of the jaw of the ultrasonic therapeutic apparatus according to the first embodiment; 
         FIG. 16  is a side view showing an insulation member of the jaw of the ultrasonic therapeutic apparatus according to the first embodiment; 
         FIG. 17  is a plan view showing an engaged state between the electrode member of the jaw and the probe distal end portion of the ultrasonic therapeutic apparatus according to the first embodiment; 
         FIG. 18  is a vertical cross-sectional view showing an engaged state between the electrode member of the jaw and the probe distal end portion of the ultrasonic therapeutic apparatus according to the first embodiment; 
         FIG. 19  is a plan view showing a living body tissue contact surface of the hold member of the jaw of the ultrasonic therapeutic apparatus according to the first embodiment; 
         FIG. 20  is a plan view showing the probe distal end portion of the ultrasonic therapeutic apparatus according to the first embodiment; 
         FIG. 21  is a longitudinal cross-sectional view showing a driving pipe of the ultrasonic therapeutic apparatus according to the first embodiment; 
         FIG. 22  is a perspective view showing a distal end portion of the driving pipe of the ultrasonic therapeutic apparatus according to the first embodiment; 
         FIG. 23  is a plan view showing the driving pipe of the ultrasonic therapeutic apparatus according to the first embodiment; 
         FIG. 24  is a cross-sectional view taken along line  24 - 24  in  FIG. 23 ; 
         FIG. 25  is a front view showing the driving pipe of the ultrasonic therapeutic apparatus according to the first embodiment; 
         FIG. 26  is a longitudinal cross-sectional view showing a state before a threaded pin is engaged in an assembly section at the proximal end portion of the sheath unit of the ultrasonic therapeutic apparatus according to the first embodiment; 
         FIG. 27  is a perspective view showing the state before the threaded pin is engaged in the assembly section at the proximal end portion of the sheath unit of the ultrasonic therapeutic apparatus according to the first embodiment; 
         FIG. 28  is a longitudinal cross-sectional view showing the state in which the threaded pin is engaged in the assembly section at the proximal end portion of the sheath unit of the ultrasonic therapeutic apparatus according to the first embodiment; 
         FIG. 29  is a perspective view showing a state prior to rotational engagement at the time when the handle unit and sheath unit of the ultrasonic therapeutic apparatus according to the first embodiment are coupled; 
         FIG. 30  is a plan view showing the state prior to rotational engagement at the time when the handle unit and sheath unit of the ultrasonic therapeutic apparatus according to the first embodiment are coupled; 
         FIG. 31  is a perspective view showing a state after the rotational engagement at the time when the handle unit and sheath unit of the ultrasonic therapeutic apparatus according to the first embodiment are coupled; 
         FIG. 32  is a plan view showing the state after the rotational engagement at the time when the handle unit and sheath unit of the ultrasonic therapeutic apparatus according to the first embodiment are coupled; 
         FIG. 33  is an explanatory view for explaining a positional relationship between a guide groove and an engaging recess portion at the coupling section between the handle unit and sheath unit of the ultrasonic therapeutic apparatus according to the first embodiment; 
         FIG. 34  is a perspective view showing a connection tube body of the sheath unit of the ultrasonic therapeutic apparatus according to the first embodiment; 
         FIG. 35  is a perspective view showing the connection tube body of the sheath unit of the ultrasonic therapeutic apparatus according to the first embodiment; 
         FIG. 36  is a side view showing a state before an attachment member is attached to a base member of a stationary handle of the handle unit of the ultrasonic therapeutic apparatus according to the first embodiment; 
         FIG. 37  is a longitudinal cross-sectional view showing a state after engagement between the handle unit and sheath unit of the ultrasonic therapeutic apparatus according to the first embodiment; 
         FIG. 38  is a cross-sectional view taken along line  38 - 38  in  FIG. 37 ; 
         FIG. 39  is a cross-sectional view taken along line  39 - 39  in  FIG. 37 ; 
         FIG. 40  is a cross-sectional view taken along line  40 - 40  in  FIG. 37 ; 
         FIG. 41A  is a vertical cross-sectional view showing a state prior to engagement of the engagement section between the handle unit and sheath unit of the ultrasonic therapeutic apparatus according to the first embodiment; 
         FIG. 41B  is a vertical cross-sectional view showing a state prior to engagement of the engagement section between the handle unit and sheath unit of the ultrasonic therapeutic apparatus according to the first embodiment; 
         FIG. 42  is a cross-sectional view taken along line  42 - 42  in  FIG. 37 ; 
         FIG. 43  is a perspective view showing an electrode hold member of the ultrasonic therapeutic apparatus according to the first embodiment; 
         FIG. 44  is a front view showing the electrode hold member of the ultrasonic therapeutic apparatus according to the first embodiment; 
         FIG. 45  is a side view showing the electrode hold member of the ultrasonic therapeutic apparatus according to the first embodiment; 
         FIG. 46  is a cross-sectional view taken along line  46 - 46  in  FIG. 37 ; 
         FIG. 47  is a cross-sectional view taken along line  47 - 47  in  FIG. 37 ; 
         FIG. 48  is a cross-sectional view taken along line  48 - 48  in  FIG. 37 ; 
         FIG. 49  is a perspective view showing an electrode member of the ultrasonic therapeutic apparatus according to the first embodiment; 
         FIG. 50  is a transverse cross-sectional view showing the electrode member of the ultrasonic therapeutic apparatus according to the first embodiment; 
         FIG. 51  is a cross-sectional view taken along line  51 - 51  in  FIG. 37 ; 
         FIG. 52  is a schematic view showing an internal structure of a cable of the transducer unit of the ultrasonic therapeutic apparatus according to the first embodiment of the present invention; 
         FIG. 53  is a perspective view that schematically shows the entire structure of a surgical operating apparatus according to a second embodiment of the present invention; 
         FIG. 54  is a perspective view showing a disassembled state of the surgical operating apparatus according to the second embodiment, with coupling sections of assembly units of the surgical operating apparatus being disconnected; 
         FIG. 55  is a side view showing a coupled state between a handle unit and a transducer unit of the surgical operating apparatus according to the second embodiment; 
         FIG. 56  is a longitudinal cross-sectional view showing an internal structure of the transducer unit of the surgical operating apparatus according to the second embodiment; 
         FIG. 57  is a plan view showing a probe unit of the surgical operating apparatus according to the second embodiment; 
         FIG. 58  is a longitudinal cross-sectional view of a sheath unit of the surgical operating apparatus according to the second embodiment; 
         FIG. 59A  is a plan view showing a driving pipe of the surgical operating apparatus according to the second embodiment; 
         FIG. 59B  is a cross-sectional view taken along line  59 B- 59 B in  FIG. 59A ; 
         FIG. 59C  is a front view showing the driving pipe shown in  FIG. 59B ; 
         FIG. 60  is a side view showing, partly in cross section, an assembled state between the driving pipe and an insulation tube of the surgical operating apparatus according to the second embodiment; 
         FIG. 61A  is a longitudinal cross-sectional view showing a proximal end portion of an outer sheath of the sheath unit of the surgical operating apparatus according to the second embodiment; 
         FIG. 61B  is a cross-sectional view taken along line  61 B- 61 B in  FIG. 61A ; 
         FIG. 61C  is a front view showing the outer sheath shown in  FIG. 61B ; 
         FIG. 61D  is a longitudinal cross-sectional view showing a proximal end portion of the outer sheath; 
         FIG. 62  is a side view showing a jaw body of a jaw of the surgical operating apparatus according to the second embodiment; 
         FIG. 63  is a side view showing an electrode member of the jaw of the surgical operating apparatus according to the second embodiment; 
         FIG. 64  is a side view showing a pad member of the jaw of the surgical operating apparatus according to the second embodiment; 
         FIG. 65  is a longitudinal cross-sectional view showing a coupled state between the jaw and the driving pipe of the surgical operating apparatus according to the second embodiment; 
         FIG. 66  is a cross-sectional view taken along line  66 - 66  in  FIG. 65 ; 
         FIG. 67  is a plan view showing that surface of the jaw of the surgical operating apparatus according to the second embodiment, which is opposed to the probe distal end portion; 
         FIG. 68  is a transverse cross-sectional view taken along line  68 - 68  in  FIG. 67 , showing a closed state between the jaw and the probe of the surgical operating apparatus according to the second embodiment; 
         FIG. 69  is a transverse cross-sectional view of a spark point, taken along line  69 - 69  in  FIG. 67 , showing a closed state between the jaw and the probe of the surgical operating apparatus according to the second embodiment; 
         FIG. 70  is a longitudinal cross-sectional view showing a proximal end portion of the sheath unit of the surgical operating apparatus according to the second embodiment; 
         FIG. 71  is a cross-sectional view taken along line  71 - 71  in  FIG. 70 ; 
         FIG. 72  is a cross-sectional view taken along line  72 - 72  in  FIG. 70 ; and 
         FIG. 73  is a longitudinal cross-sectional view showing a state before assembly of a knob member of the surgical operating apparatus according to the second embodiment. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     A first embodiment of the present invention will now be described with reference to  FIG. 1  to  FIG. 52 .  FIG. 1  schematically shows the entire structure of a handpiece  1  of an ultrasonic therapeutic apparatus which is a surgical operating apparatus according to the first embodiment. The ultrasonic therapeutic apparatus of the present embodiment is an ultrasonic coagulation/incision apparatus. This ultrasonic coagulation/incision apparatus can perform therapeutic treatment, such as incision, resection or coagulation, of a living body tissue by making use of ultrasonic, and can also perform therapeutic treatment by high-frequency waves. 
     The handpiece  1 , as shown in  FIG. 2 , comprises four units, namely, a transducer unit  2 , a probe unit (probe section)  3 , a handle unit (operation section)  4  and a sheath unit (sheath section)  5 . These units are detachably coupled. 
     As shown in  FIG. 4 , an ultrasonic transducer  6  for generating ultrasonic vibration by a piezoelectric oscillator, which converts an electric current to ultrasonic vibration, is built in the transducer unit  2 . An outside of the ultrasonic transducer  6  is covered with a cylindrical transducer cover  7 . As shown in  FIG. 1 , a cable  9  for supplying an electric current for generating ultrasonic vibration from a power supply device body  8  extends from a rear end of the transducer unit  2 . 
     A proximal end portion of a horn  10 , which increases the amplitude of ultrasonic vibration, is coupled to a front end portion of the ultrasonic transducer  6 . A screw hole portion  10   a  for attaching the probe is formed at a distal end portion of the horn  10 . 
       FIG. 5  shows the external appearance of the entire probe unit  3 . The probe unit  3  is designed such that the entire length thereof may become an integer number of times of half-wave length of the ultrasonic vibration. The probe unit  3  has a distal end portion and a proximal end portion, and includes a metallic rod-shaped vibration transmission member  11  having a long axis. A proximal end portion of the vibration transmission member  11  is provided with a screw portion  12  which is to be engaged with the screw hole portion  10   a  of the horn  10 . The screw portion  12  is engaged with the screw hole portion  10   a  of the horn  10  of the transducer unit  2 . Thereby, the probe unit  3  and the transducer unit  2  are assembled. At this time, a first high-frequency electric path  13 , through which a high-frequency current is transmitted, is formed in the coupled body of the ultrasonic transducer  6  and the probe unit  3 . 
     A probe distal end portion  3   a  is provided at a distal end portion of the vibration transmission member  11 . The probe distal end portion  3   a  is formed in a substantially J-shaped curved form. The probe distal end portion  3   a  constitutes a first electrode section which is one of bipolar electrodes. The cross-sectional area of the probe unit  3  is decreased in the axial direction at several nodes of vibration in the axial direction, so that an amplitude necessary for therapeutic treatment can be obtained at the probe distal end portion  3   a . Rubber rings  3   b  (see  FIG. 7 ), which are formed of elastic material in an annular shape, are attached to several positions of nodes of vibration along the axial direction of the probe unit  3 . The rubber rings  3   b  prevent interference between the probe unit  3  and the sheath unit  5 . 
     A flange portion  14  is provided at the position of the node of vibration on the most proximal end side in the axial direction of the probe unit  3 . As shown in  FIG. 6 , engaging recess portions  15  each having a key groove shape are formed on the outer peripheral surface of the flange portion  14  at three positions in the circumferential direction thereof. 
       FIG. 8A  shows a distal end portion of the sheath unit  5 , and  FIG. 9A  shows a proximal end portion of the sheath unit  5 . As shown in  FIG. 8A , the sheath unit  5  includes a sheath body  16 , which is formed of a cylindrical body, and a jaw  17  which is provided at a distal end of the sheath body  16 . The sheath body  16  includes a metallic sheath  18  which is an outer cylinder, and a metallic driving pipe  19  which is an inner cylinder. The driving pipe  19  is axially movably inserted in the sheath  18 . 
     As shown in  FIG. 8A , the outer peripheral surface of the sheath  18  is covered with an outer coating  18   a  which is formed of an insulating material such as a resin. An insulation tube  24 , which is formed of an insulating material, is provided on the inner peripheral side of the driving pipe  19 . 
     As shown in  FIGS. 10 to 12 , a pair of right and left projection portions  25  are provided at a distal end portion of the sheath  18  so as to project in a forward direction of the sheath  18 . A proximal end portion of the jaw  17  is rotatably attached to the projection portions  25  via a support pin  27 . When the probe unit  3  and the sheath unit  5  are assembled, the jaw  17  is positioned to be opposed to the probe distal end portion  3   a  of the probe unit  3 . 
     As shown in  FIG. 8B , the jaw  17  is formed in a substantially J-shaped curved form, which corresponds to the curved shape of the probe distal end portion  3   a , in accordance with the curved shape of the probe distal end portion  3   a  of the probe unit  3 . The jaw  17  is configured to be rotated about the support pin  27  by the advancing/retreating movement of the driving pipe  19  in the axial direction. A therapeutic section  1 A of the handpiece  1  is constituted by the jaw  17  and the probe distal end portion  3   a.    
     The jaw  17  includes a metallic jaw body  201  (see  FIG. 14 ) which is an electrically conductive member, and a hold member  202  which is attached to the jaw body  201 . The hold member  202  is composed of an electrode member  203  (see  FIG. 15 ) for high-frequency therapeutic treatment, and an insulation member  204  (see  FIG. 16 ) for ultrasonic therapeutic treatment. The electrode member  203  constitutes a second electrode section which is the other electrode of the bipolar electrodes. 
     As shown in  FIGS. 17 and 18 , a groove portion  205 , which is formed in accordance with the curved shape of the probe distal end portion  3   a , is formed on the lower surface of the electrode member  203 . An engaging surface  206 , which is to be engaged with the probe distal end portion  3   a , is formed by the groove portion  205 . A groove width W of the groove portion  205  is set in consideration of the diameter dimension of the probe distal end portion  3   a . Specifically, the groove width W is set to be greater than the diameter dimension of the probe distal end portion  3   a  by a predetermined ratio, thereby preventing contact between the engaging surface  206  of the electrode member  203  and the probe distal end portion  3   a.    
     Inclined surfaces  205   a , which are configured to gradually increase the groove width toward a lower-side opening surface, as shown in  FIG. 18 , are formed on both side wall surfaces of the groove portion  205 . In addition, as shown in  FIG. 19 , tooth portions  203   b  for preventing a slip are formed on both side walls  203   a  of the groove portion  205  on the lower-side opening surface side. The tooth portions  203   b  form a slip-preventing section for preventing a slip of a clamped object between the probe distal end portion  3   a  and the jaw  17  when the jaw  17  and probe distal end portion  3   a  are engaged. A wall thickness T of the electrode member  203  is properly determined in consideration of the rigidity and coagulation performance. 
     Further, in the electrode member  203 , a notch portion  205   b  is formed at a bottom portion of the groove portion  205 . The notch portion  205   b  is formed in accordance with the curved shape of the probe distal end portion  3   a . A pad member  207 , which is formed of an insulating material, for instance, a resin material such as polytetrafluoroethylene, is disposed in the notch portion  205   b . As shown in  FIG. 18 , the pad member  207  is a probe contact member which is in contact with the probe distal end portion  3   a . The probe distal end portion  3   a  comes in contact with the pad member  207 , thus securing a clearance between the second electrode section of the electrode member  203  and the probe distal end portion  3   a.    
     In addition, the jaw  17  has a block-shaped distal end chip  208  at a distal end portion of the engaging surface  206  for engagement with the probe distal end portion  3   a . The distal end chip  208  is formed of an insulating material, for instance, a resin material such as polytetrafluoroethylene. When the jaw  17  and probe distal end portion  3   a  are engaged, a positional displacement relative to the probe distal end portion  3   a  is tolerated by the distal end chip  208 . 
     As shown in  FIG. 16 , in the insulation member  204 , the distal end chip  208  is coupled to the distal end portion of the pad member  207 . In the insulation member  204 , the pad member  207  and the distal end chip  208  are provided as one body. 
     The electrode member  203  and insulation member  204  are integrally assembled to form the hold member  202 . A hook-shaped engaging portion  209  is formed at a rear end portion of the insulation member  204 . In addition, a distal end chip engaging portion  203   c , which engages the distal end chip  208 , is formed at the distal end portion of the electrode member  203 . When the electrode member  203  and the insulation member  204  are assembled, the distal end chip  208  is engaged with the distal end chip engaging portion  203   c , and also the engaging portion  209  at the rear end portion of the insulation member  204  is engaged with the rear end portion of the electrode member  203  in the state in which the pad member  207  is inserted in the notch portion  205   b  of the groove portion  205  of the electrode member  203 . 
     A projection portion  210  for attachment is provided on that side of the hold member  202 , which is opposed to the engaging surface  206  for engagement with the probe distal end portion  3   a . A screw insertion hole  211  is formed in the projection portion  210 . 
     A hold member engaging portion  212 , which engages the projection portion  210  of the hold member  202 , is provided on a distal end side of the jaw body  201 . The hold member  202  is engaged with the hold member engaging portion  212 . Further, a screw hole  213  is formed in side wall portions of the hold member engaging portion  212 . As shown in  FIG. 18 , when the hold member engaging portion  212  of the jaw body  201  and the projection portion  210  of the hold member  202  are engaged, a fixing screw  214 , which is engaged in the screw hole  213  of the jaw body  201 , is inserted in the screw insertion hole  211  of the hold member  202 . In this state, the fixing screw  214  is fastened in the screw hole  213 , and thereby the hold member  202  is attached to the jaw body  201 . The electrode member  203  of the hold member  202  and the jaw body  201  are electrically connected via the fixing screw  214 . 
     A proximal end portion of the jaw body  201  has two-forked arm portions  215   a  and  215   b . The respective arm portions  215   a  and  215   b  have extension portions  215   a   1  and  215   b   1 , which extend obliquely downward from a position of a center line of the jaw body  201 . The extension portions  215   a   1  and  215   b   1  are rotatably attached by the support pin  27  to the right and left projection portions  25  at the distal end portion of the sheath  18 . 
     A coupling pin insertion hole  216  is formed in a proximal portion of each of the two arm portions  215   a  and  215   b . A coupling pin  217  for coupling the jaw body  201  and the driving pipe  19  is inserted in the coupling pin insertion holes  216 . The jaw body  201  and the driving pipe  19  are electrically connected via the coupling pin  217 . 
     Thereby, the driving force of the driving pipe  19  is transmitted to the jaw  17  via the coupling pin  217  by the advancing/retreating in the axial direction of the driving pipe  19 . Accordingly, the jaw  17  is rotated about the support pin  27 . In this case, when the driving pipe  19  is pulled rearward, the jaw  17  is rotated about the support pin  27  and driven (to an open position) in a direction away from the probe distal end portion  3   a . Conversely, when the driving pipe  19  is pushed forward, the jaw  17  is rotated about the support pin  27  and driven (to a closed position) in a direction toward the probe distal end portion  3   a . A living body tissue is held between the jaw  17  and the probe distal end portion  3   a  of the probe unit  3  when the jaw  17  is rotated to the closed position. 
     The therapeutic section  1 A of the handpiece  1  is constituted by the jaw  17  and the probe distal end portion  3   a  of the probe unit  3 . The therapeutic section  1 A is configured to selectively perform a plurality of therapeutic functions, for example, two therapeutic functions (a first therapeutic function and a second therapeutic function) in this embodiment. For instance, the first therapeutic function is set to be a function of simultaneously outputting an ultrasonic therapeutic output and a high-frequency therapeutic output. The second therapeutic function is set to be a function of outputting only the high-frequency therapeutic output. 
     The first therapeutic function and second therapeutic function of the therapeutic section  1 A are not limited to the above-described configuration. For example, the first therapeutic function may be set to be a function of outputting an ultrasonic therapeutic output in a maximum output state, and the second therapeutic function may be set to be a function of outputting the ultrasonic therapeutic output in a preset arbitrary output state which is lower than the maximum output state. 
     As shown in  FIGS. 17 and 19 , the jaw  17  has, at a distal end portion of the groove portion  205 , a distal-end-side groove width varying section  205   t   1  which has such a tapering shape that the groove width of the groove portion  205  gradually increases toward the distal end. In addition, the jaw  17  has, at a proximal end portion of the groove portion  205 , a proximal-end-side groove width varying section  205   t   2  which has such a tapering shape that the groove width of the groove portion  205  gradually increases toward the proximal end. In the distal-end-side groove width varying section  205   t   1  and proximal-end-side groove width varying section  205   t   2 , a positional displacement in assembly between the probe distal end portion  3   a  and the electrode member  203  of the jaw  17  can be tolerated in a case where the assembly position of the electrode member  203  of the jaw  17  is slightly displaced, relative to the probe distal end portion  3   a , in the axial direction of the sheath unit  5  when the probe unit  3  and the sheath unit  5  are assembled. 
       FIG. 21  shows the driving pipe  19 . The driving pipe  19  includes a tubular body section  221  and an operating section  222 . The body section  221  is inserted in the sheath  18  so as to be slidable in the axial direction of the sheath  18 . The operating section  222  is disposed on the distal end side of the body section  221 , and includes a connection section  223  which is connected to the jaw  17 . 
     As shown in  FIG. 22 , the peripheral wall of a tubular distal end portion of the body section  221  includes a crescent-shaped arcuate cross-sectional portion  224 , which is formed by leaving a substantially crescent-shaped arcuate cross-sectional portion over a predetermined length in the axial direction, and cutting out the other portion. As shown in  FIG. 23 , the arcuate cross-sectional portion  224  includes a taper portion  225  with a tapered distal end portion, which is gradually tapered toward the distal end side. As shown in  FIG. 22  and  FIG. 25 , a U-shaped portion  226  having a U-shaped cross section is formed at a distal end of the taper portion  225 . The operating section  222  is constituted by the U-shaped portion  226 . 
     As shown in  FIG. 22 , the U-shaped portion  226  has two side surfaces  226   a  and  226   b , which are opposed to each other, and a connecting surface  226   c  which connects the two side surfaces  226   a  and  226   b . The connection section  223  is formed in each of the two side surfaces  226   a  and  226   b  of the U-shaped portion  226 . 
     The operating section  222  has a slit  227  extending in the axial direction of the sheath  18  in a distal end portion of the connecting surface  226   c . As shown in  FIG. 23 , the slit  227  has a terminal end portion  227   a  which is located at a position corresponding to a proximal end portion of the taper portion  225 . 
     As shown in  FIG. 8A , the insulation tube  24  includes a projection portion  228  which projects forward of the body section  221  of the driving pipe  19 . The projection portion  228  extends up to a rear end position of the U-shaped portion  226 . 
     Further, a proximal end portion of the insulation tube  24  extends to a proximal end side of the sheath body  16 . The driving pipe  19  and probe unit  3  are electrically insulated by the insulation tube  24 . 
       FIG. 9  shows a proximal end portion of the sheath body  16 . The proximal end portion of the sheath  18  includes a flare portion  229  which has a greater inside diameter than the other portion. A proximal end portion of the driving pipe  19  extends more rearward than the flare portion  229  of the sheath  18 . 
     Seal means  230  for effecting sealing between the sheath  18  and the driving pipe  19  is provided between the flare portion  229  and the driving pipe  19 . The seal means  230  includes two backup rings  231  and  232  and one O ring  233 . The two backup rings  231  and  232  are disposed between the flare portion  229  and the driving pipe  19  in the state in which the two backup rings  231  and  232  are paired in a back-and-forth direction along the axis of the sheath  18 . The O ring  233  is provided between the backup rings  231  and  232  so as to be movable in the axial direction of the sheath  18 . 
     In addition, the proximal end portion of the sheath body  16  is provided with an attachment/detachment mechanism section  31  for attachment/detachment to/from the handle unit  4 . The attachment/detachment mechanism section  31  includes a cylindrical large-diameter handle member  32  which is formed of a resin material, a guide cylindrical body (first tubular member)  33  which is formed of a metallic cylindrical body, and a cylindrical connection tube body (second tubular member)  34  which is formed of a resin material. 
     The guide cylindrical body  33  includes a tubular body  33   a  which is fitted on the flare portion  229  of the proximal end portion of the sheath  18  and extends rearward. A distal end portion of the tubular body  33   a  is provided with a large-diameter  33   b  which has a greater outside diameter than the other portion thereof. The handle member  32  is fitted on the large-diameter portion  33   b . A connection flange portion  33   c , which projects outward, is formed on an outer peripheral surface of a rear end portion of the guide cylindrical body  33 . 
     As shown in  FIG. 27 , an outer peripheral wall portion of the tubular  33   a  has an elongated slit  234  extending in the axial direction of the sheath  18 . In addition, on the rear end portion side of the guide cylindrical body  33 , a distal end portion of the connection tube body  34  is inserted so as to be slidable in the axial direction of the sheath  18 . A proximal end portion of the driving pipe  19  is fitted and inserted inside the inner peripheral surface of the distal end portion of the connection tube body  34 . 
     As shown in  FIG. 28 , a threaded pin (projection body)  235  is fixed to a proximal end portion of the driving pipe  19 . As shown in  FIG. 26 , the threaded pin  235  includes a male screw member  236 . A threaded hole portion  237 , which is engaged with a male screw portion  236   a  of the threaded pin  235 , is formed in the connection tube body  34 . 
     A large-diameter portion  236   b , which has a greater diameter than the male screw portion  236   a , is formed on a head portion of the screw member  236 . The large-diameter portion  236   b  of the threaded pin  235  is an engaging portion which is engaged in the slit  234  of the guide cylindrical body  33 . 
     A small-diameter portion  238 , which has a smaller diameter than the male screw portion  236   a , is provided on the threaded pin  235  so as to project on a side opposite to the head portion of the screw member  236 . The small-diameter portion  238  is inserted and fitted in a fixing hole  239  which is formed in a proximal end portion of the driving pipe  19 . Thereby, the male screw portion  236   a  of the threaded pin  235  is engaged in and passed through the screw hole portion  237  of the connection tube body  34 , and a coupling body  240 , in which the driving pipe  19  and the connection tubular body  34  are coupled, is formed. Further, the large-diameter portion  236   b  of the threaded pin  235  is engaged with the slit  234  of the guide cylindrical body  33 , and thereby the coupling body  240  is coupled to the guide cylindrical body  33  so as to be movable as one body along the slit  234  in the axial direction of the sheath  18 . 
     A fixing section  35  of the guide cylindrical body  33  is formed by an engaging section between the handle member  32  and the large-diameter portion  33   b  of the guide cylindrical body  33 . Further, in the handle member  32 , an attachment/detachment section  36  for attachment/detachment to/from the handle unit  4  is disposed on the rear side of the fixing section  35 . 
       FIG. 29  to  FIG. 32  show the structure of the attachment/detachment part between the handle member  32  and the handle unit  4 . As shown in  FIGS. 30 to 32 , the attachment/detachment section  36  of the handle member  32  has a guide groove  41  with an inclined surface, and an engaging recess portion  42 . The guide groove  41  is provided to extend in a circumferential direction on the outer peripheral surface of the proximal end portion of the handle member  32 . In addition, the guide groove  41  has a tapered inclined surface with an outside diameter decreasing toward the rear end portion side of the handle member  32 . 
     As shown in  FIG. 33 , the engaging recess portion  42  is formed at one end portion of the guide groove  41 . The engaging recess portion  42  is formed of a recess portion having a smaller diameter than the inclined surface of the guide groove  41 . The engaging recess portion  42  is configured such that the engaging lever  43  (to be described later) on the handle unit  4  side is disengageably engaged in the engaging recess portion  42 .  FIGS. 31 and 32  show the state in which the engaging lever  43  is engaged in the engaging recess portion  42 , and  FIGS. 29 and 30  show the disengaged state in which the engaging lever  43  is pulled out of the engaging recess portion  42 . 
     As shown in  FIGS. 34 and 35 , a proximal end portion of the connection tube body  34  has two guide grooves  44  which are used at a time of attachment/detachment to/from the handle unit  4  side. The guide grooves  44  are configured such that two engaging pins  45  (to be described later) on the handle unit  4  side are disengageably engaged in the guide grooves  44 , respectively. An engaging groove  44   a , which restricts movement of the engaging pin  45  in the axial direction of the sheath body  16 , is formed at a terminal end portion of the guide groove  44 . 
     As shown in  FIG. 9B , the connection flange portion  33   c  of the guide cylindrical body  33  has a non-circular engaging portion  46 . The engaging portion  46  has three cut-out flat-surface portions  46   a  at a plurality of locations on the circular outer peripheral surface of the connection flange portion  33   c , for example, at three locations in this embodiment. Corner portions  46   b , each having a greater diameter than the flat-surface portion  46   a , are formed at connection parts between the three flat-surface portions  46 . Thereby, the engaging portion  46  with a substantially triangular cross section is formed on the connection flange portion  33   c . It is not necessary that the non-circular engaging portion  46  have a substantially triangular shape. The non-circular engaging portion  46  may have any other non-circular shape, for instance, a polygon such as a rectangle or a pentagon. 
     As shown in  FIG. 3 , the handle unit  4  mainly includes a stationary handle  47 , a hold cylinder  48 , a movable handle  49  and a rotational operation knob  50 . The hold cylinder  48  is provided on the upper part of the stationary handle  47 . A switch hold section  51  is provided between the stationary handle  47  and the hold cylinder  48 . As shown in  FIG. 36 , the switch hold section  51  includes a switch attachment section  52  which is fixed to a lower end portion of the hold cylinder  48 , and a cover member  53  which is fixed to an upper end portion of the stationary handle  47 . 
     As shown in  FIG. 37 , the switch attachment section  52  has a switch attachment surface  52   a  on a front side thereof, to which a plurality of hand switches, for example, two hand switches (first switch  54  and second switch  55 ) in the present embodiment, are attached. The first switch  54  and second switch  55  are switches for selecting therapeutic functions of the therapeutic section  1 A of the handpiece  1 . 
     In the switch attachment section  52 , the first switch  54  and second switch  55  are arranged in the up-and-down direction. The first switch  54  is disposed on an upper side of the switch attachment surface  52   a , and is set to be a switch which selects a first therapeutic function that is frequently used among the plural therapeutic functions. The second switch  55  is disposed on a lower side of the switch attachment surface  52   a , and is set to be a switch which selects another second therapeutic function of the plural therapeutic functions. 
     As shown in  FIG. 2 , the movable handle  49  has a substantially U-shaped arm section  56  at an upper part thereof. The U-shaped arm section  56  includes two arms  56   a  and  56   b . The movable handle  49  is assembled to the hold cylinder  48  in the state in which the hold cylinder  48  is inserted between the two arms  56   a  and  56   b.    
     Each of the arms  56   a  and  56   b  has a support pin  57  and an operation pin  58 . As shown in  FIG. 36 , a pin receiving hole portion  59  and a window portion  60  are formed in each of both side portions of the hold cylinder  48 . The support pin  57  of each arm  56   a ,  56   b  is inserted in the pin receiving hole portion  59  of the hold cylinder  48 . Thereby, an upper end portion of the movable handle  49  is rotatably supported on the hold cylinder  48  via the support pins  57 . 
     Ring-shaped finger hook portions  61  and  62  are provided on lower end portions of the stationary handle  47  and movable handle  49 , respectively. By hooking the fingers on the finger hook portions  61  and  62  and holding them, the movable handle  49  rotates via the support pins  57  and the movable handle  49  is opened/closed relative to the stationary handle  47 . 
     The operation pins  58  of the movable handle  49  extend into the hold cylinder  48  through the window portions  60  of the hold cylinder  48 . An operation force transmission mechanism  63 , which transmits an operation force of the movable handle  49  to the driving pipe  19  of the jaw  17 , is provided inside the hold cylinder  48 . 
     As shown in  FIG. 37 , the operation force transmission mechanism  63  mainly comprises a metallic cylindrical spring receiving member  64  and a resin-made slider member  65 . The spring receiving member  64  is disposed coaxially with the center axis of the hold cylinder  48 , and extends in the same direction as the direction of insertion of the probe unit  3 . 
     A coil spring  67 , the slider member  65 , a stopper  68  and a spring receiver  69  are provided on an outer peripheral surface of the spring receiving member  64 . A front end portion of the coil spring  67  is fixed to the spring receiver  69 . The stopper  68  restricts the position of movement of a rear end side of the slider member  65 . The coil spring  67  is disposed between the spring receiver  69  and the slider member  65  with a fixed amount of mounting force. 
     An annular engaging groove  65   a  is formed in a circumferential direction in an outer peripheral surface of the slider member  65 . As shown in  FIG. 38 , the operation pins  58  of the movable handle  49  are inserted and engaged in the engaging groove  65   a . If the movable handle  49  is held and the movable handle  49  is closed relative to the stationary handle  47 , the operation pins  58  rotate about the support pins  57  in accordance with the rotational operation of the movable handle  49  at this time. The slider member  65 , which is in interlock with the rotation of the support pins  57 , moves forward in the axial direction. At this time, the spring receiving member  64 , which is coupled to the slider member  65  via the coil spring  67 , moves forward/backward together with the slider member  65 . As shown in  FIG. 40 , a pair of engaging pins  45 , which are used when the sheath unit  5  and the handle unit  4  are attached/detached, are fixed to a distal end portion of the spring receiving member  64 . Thereby, the operation force of the movable handle  49  is transmitted to the connection tube body  34  of the sheath unit  5  via the pair of engaging pins  45 , and the driving pipe  19  of the jaw  17  moves forward. Thereby, the jaw body  201  of the jaw  17  rotates via the support pin  27 . 
     Further, when a living body tissue is clamped between the hold member  202  of the jaw  17  and the probe distal end portion  3   a  of the probe unit  3  by this operation, the hold member  202  rotates over a certain angle about the pin  214  in accordance with the bending of the probe distal end portion  3   a  so that force uniformly acts over the entire length of the hold member  202 . In this state, ultrasonic is output and a living body tissue, such as a blood vessel, can be coagulated or cut. 
     An annular bearing portion  70  is formed at a front end portion of the hold cylinder  48 . The bearing portion  70  is metallic, and a cylindrical rotation transmission member  71  is coupled to the bearing portion  70  rotatably about the axis. The rotation transmission member  71  includes a projecting portion  72  which projects forward of the bearing portion  70 , and a large-diameter portion  73  which extends to the inner side of the hold cylinder  48  from the bearing portion  70 . 
     The rotational operation knob  50  is fitted and fixed on the projecting portion  72 . The engaging lever  43  is provided at the front end portion of the rotational operation knob  50 . An intermediate portion of the engaging lever  43  is rotatably coupled to the projecting portion  72  via a pin  74 . A proximal end portion of the engaging lever  43  extends to the inside of a lever receiving recess portion  75  which is formed in a front surface of the rotational operation knob  50 . 
     An operation button  76  for operating the engaging lever  43  in such a direction as to disengage the engaging lever  43  is provided on an outer peripheral surface of the front end portion of the rotational operation knob  50 . An operation pin  77 , which is disposed downward, is provided so as to project from the operation button  76 . The operation pin  77  extends to the inside of the lever receiving recess portion  75  through a wall hole of the rotational operation knob  50 . A proximal end portion of the engaging lever  43  is rotatably coupled to a lower end portion of the operation pin  77  via a pin  78 . 
     A removal prevention ring  80  for the rotational operation knob  50  is provided on a distal end portion of the projecting portion  72 . A male threaded portion  79  is formed on the distal end portion of the projecting portion  72 . A female threaded portion  80   a , which is to be meshed with the male threaded portion  79 , is formed on an inner peripheral surface of the removal prevention ring  80 . The female threaded portion  80   a  of the removal prevention ring  80  is meshed and engaged with the male threaded portion  79  of the projecting portion  72 , and thereby the rotational operation knob  50  is fixed to the rotation transmission member  71 . 
     As shown in  FIG. 39 , the spring receiver  69  of the spring receiving member  64  is provided with four metallic positioning pins  81  which project radially outward. An elongated engaging hole portion  82 , in which one pin  81  of the spring receiving member  64  is inserted, is formed in the large-diameter portion  73  of the rotation transmission member  71 . The engaging hole portion  82  extends in the same direction as the direction of insertion of the probe unit  3 . Thereby, when the movable handle  49  is operated, the pin  81  is moved along the engaging hole portion  82  and thus the advancing/retreating movement of the spring receiving member  64  is prevented from being transmitted to the rotation transmission member  71 . 
     On the other hand, when the rotational operation knob  50  is rotated, the rotational movement of the rotation transmission member  71 , which rotates together with the rotational operation knob  50 , is transmitted to the spring receiving member  64  via the pin  81 . Thereby, when the rotational operation knob  50  is rotated, the assembly unit of the rotation transmission member  71 , pin  81 , spring receiving member  64 , slider member  65  and coil spring  67  within the hold cylinder  48  is rotated together with the rotational operation knob as one body about the axis thereof. 
     Engaging means  94 , which is disengageably engaged with the connection flange portion  33   c  of the sheath unit  5 , is provided on the inner peripheral surface of the rotation transmission member  71 .  FIGS. 41A and 41B  show the engaging means  94 . The engaging means  94  includes an insertion hole portion  94   a  in which the connection flange portion  33   c  is inserted when the sheath unit  5  and handle unit  4  are coupled, and an electrically conductive rubber ring (urging means)  94   b  which is disposed within the insertion hole portion  94   a.    
     The shape of the inner peripheral surface of the electrically conductive rubber ring  94   b  is substantially the same as the shape of the engaging portion  46  of the connection flange portion  33   c . Specifically, the inner peripheral surface of the electrically conductive rubber ring  94   b  has three cut-out flat-surface portions  94   b   1  at a plurality of locations on the circular outer peripheral surface, for example, at three locations in this embodiment, and three corner portions  94   b   2  which are located at connection parts between the three flat-surface portions  94   b   1  and have greater diameters than the flat-surface portions  94   b   1 . Thereby, the electrically conductive rubber ring  94   b  has a substantially triangular cross-sectional shape. Thus, as shown in  FIG. 41A , the electrically conductive rubber ring  94   b  is held in a natural, non-compressed position in the positional state in which the inner peripheral surface shape of the electrically conductive rubber ring  94   b  corresponds to the engaging portion  46  of the connection flange portion  33   c , that is, in the state in which the three corner portions  46   b  of the connection flange portion  33   c  correspond in position to the three corner portions  94   b   2  of the electrically conductive rubber ring  94   b . On the other hand, by rotating the handle unit  4  and the sheath unit  5  relative to each other about the center axis of the sheath unit  5 , the position of the electrically conductive rubber ring  94   b  is switched to a pressure contact position, as shown in  FIG. 41B , where the electrically conductive rubber ring  94   b  is pressed on the three corner portions  46   b  of the connection flange portion  33   c . At this time, the three corner portions  46   b  of the connection flange portion  33   c  are put in contact with, and pressed by, the three flat-surface portions  94   b   1  of the electrically conductive rubber ring  94   b.    
     In the present embodiment, at the time of coupling the sheath unit  5  and handle unit  4 , when the connection flange portion  33   c  of the sheath unit  5  is inserted straight into the electrically conductive rubber ring  94   b  (see  FIG. 29  and  FIG. 30 ), the electrically rubber ring  94   b  is held in the natural, non-compressed position, as shown in  FIG. 41A . At this time, the engaging lever  43  on the handle unit  4  side is held in the state in which the engaging lever  43  rests on the inclined surface of the guide groove  41  of the handle member  32  of the sheath unit  5 . Subsequently, the handle member  32  of the sheath unit  5  is rotated about the axis, relative to the handle unit  4 . Thereby, as shown in  FIG. 31  and  FIG. 32 , the engaging lever  43  on the handle unit  4  side is inserted and engaged in the engaging recess portion  42  at one end portion of the guide groove  41 . At this time, as shown in  FIG. 41B , the electrically conductive rubber ring  94   b  is switched to the pressure contact position where the electrically conductive rubber ring  94   b  is put in pressure contact with the three corner portions  46   b  of the connection flange portion  33   c . Thereby, a sheath-unit-side electric path  40  (formed between the guide cylindrical body  33 , fixing screw  39 , coupling pipe  38 , sheath  18 , distal end cover  25 , support pin  27  and jaw body  28 ) and a handle-unit-side electric path  95  (formed between an electrical contact member  96 , spring receiving member  64 , positioning pin  81  and rotation transmission member  71 ) are electrically connected via the electrically conductive rubber ring  94   b . In this case, a second high-frequency electric path  97 , which transmits a high-frequency current, is formed in the coupled body of the sheath unit  5  and handle unit  4 . 
     As shown in  FIG. 42 , the handle unit  4  includes a tubular member  98  which is formed of an insulating material on the inner peripheral surface of the spring receiving member  64 . The tubular member  98  is fixed on the inner peripheral surface of the spring receiving member  64 . Thereby, when the probe unit  3  and the handle unit  4  are connected, the first high-frequency electric path  13  and the second high-frequency electric path  97  are insulated by the tubular member  98 . 
     An inner peripheral surface of the tubular member  98  has three engaging projection portions  99  which correspond to the three engaging recess portions  15  (see  FIG. 6 ) of the flange portion  14  of the probe unit  3 . When the probe unit  3  and handle unit  4  are connected, the three engaging projection portions  99  of the tubular member  98  are disengageably engaged with the three engaging recess portions  15  of the flange portion  14  of the probe unit  3 . Thereby, the rotational-directional position between the probe unit  3  and the tubular member  98  of the handle unit  4  is restricted. Hence, when the rotational operation knob  50  is rotated, the coupled body of the probe unit  3  and transducer unit  2  is rotated as one body together with the assembly unit within the hold cylinder  48 . 
     The engaging section between the flange portion  14  of the probe unit  3  and the tubular member  98  is not limited to the above-described structure. For example, the tubular member  98  may be formed to have a D-shaped cross section, and the flange portion  14  of the probe unit  3  may be formed to have a corresponding D-shaped cross section. 
       FIGS. 43 to 45  show a cylindrical contact-point unit  66  which is assembled to the hold cylinder  48 . The contact-point unit  66  includes a cylindrical electrode hold member  83  which is formed of a resin. As shown in  FIG. 45 , the electrode hold member  83  includes three (first to third) electrode receiving sections  84 ,  85  and  86  with different outside diameters. The first electrode receiving section  84  on the distal end side has a smallest diameter, and the third electrode receiving section  86  on the rear end side has a greatest diameter. 
       FIG. 46  shows the first electrode receiving section  84 ,  FIG. 47  shows the second electrode receiving section  85 , and  FIG. 48  shows the third electrode receiving section  86 . 
     As shown in  FIG. 46 , the first electrode receiving section  84  has one contact-point member fixing hole  84   a , and two through-holes  84   b  and  84   c . A center line of the two through-holes  84   b  and  84   c  is set to be perpendicular to a center line of the contact-point member fixing hole  84   a.    
     Similarly, as shown in  FIG. 47 , the second electrode receiving section  85  has one contact-point member fixing hole  85   a , and two through-holes  85   b  and  85   c . As shown in  FIG. 48 , the third electrode receiving section  86  has one contact-point member fixing hole  86   a , and two through-holes  86   b  and  86   c.    
     The positions of the contact-point member fixing hole  84   a  of the first electrode receiving section  84 , the contact-point member fixing hole  85   a  of the second electrode receiving section  85  and the contact-point member fixing hole  86   a  of the third electrode receiving section  86  are displaced in the circumferential direction of the electrode hold member  83 . 
       FIG. 49  and  FIG. 50  show electrode members  87 A,  87 B and  87 C which are assembled to the first to third electrode receiving sections  84 ,  85  and  86 . These electrode members  87 A,  87 B and  87 C are formed in the same shape. In the description below, only the electrode member  87 A, which is assembled to the first electrode receiving section  84 , is described. The common parts of the electrode members  87 B and  87 C of the other second and third electrode receiving sections  85  and  86  are denoted by like reference numerals, and a description thereof is omitted. 
     The electrode member  87 A includes one straight stationary portion  87   a  and two bend portions  87   b  and  87 C. One bend portion  87   b  is disposed at one end of the straight stationary portion  87   a , and the other bend portion  87   c  is disposed at the other end of the straight stationary portion  87   a . Thereby, as shown in  FIG. 49 , the electrode member  87 A is formed and bent in a substantially U shape. 
     A hole  88  and an L-shaped wiring connection portion  89  are provided at a central position of the stationary portion  87   a . Inwardly curved waist portions  90  are formed at central positions of the two bend portions  87   b  and  87   c.    
     When the first electrode receiving section  84  and the electrode member  87 A are assembled, a fixing pin  91  is inserted in the hole  88  of the stationary portion  87   a  of the electrode member  87 A and in the contact-point member fixing hole  84   a  of the first electrode receiving section  84 . The electrode member  87 A is fixed to the first electrode receiving section  84  by the fixing pin  91 . At this time, the waist portion  90  of one bend portion  87   b  of the electrode member  87 A is disposed in one through-hole  84   b  of the first electrode receiving section  84 , and the waist portion  90  of the other bend portion  87   c  of the electrode member  87 A is disposed in the other through-hole  84   c . The same applies when the electrode member  87 B is assembled to the second electrode receiving section  85  and the electrode member  87 C is assembled to the third electrode receiving section  86 . 
     As shown in  FIG. 51 , a large-diameter fixing flange portion  83   a  is formed at a rear end portion of the electrode hold member  83  of the contact-point unit  66 . Engaging projection portions  83   b  are provided to project from the outer peripheral surface of the fixing flange portion  83   a  at a plurality of locations, for example, at three locations in this embodiment. Engaging recess portions  48   a  are formed in an inner peripheral surface of the rear end portion of the hold cylinder  48  at positions corresponding to the three engaging projection portions  83   b  of the stationary flange portion  83   a . In the case where the electrode hold member  83  is assembled in the hold cylinder  48 , the three engaging projection portions  83   b  of the stationary flange portion  83   a  are inserted, engaged and fixed in the engaging recess portions  48   a  of the hold cylinder  48 . Thereby, the rotation of the electrode hold member  83  about the axis thereof, relative to the hold cylinder  48 , is restricted. 
     A stepped portion  43   b , which comes in contact with the fixing flange portion  83   a  of the electrode hold member  83 , is formed on the hold cylinder  48 . The electrode hold member  83  is fixed to the hold cylinder  48  by a fixing screw  48   c  in the state in which the fixing flange portion  83   a  of the electrode hold member  83  abuts upon the stepped portion  43   b . Thereby, the axial movement of the electrode hold member  83 , relative to the hold cylinder  48 , is restricted. 
     End portions of three wiring lines  93   a  to  93   c , which are assembled in the switch hold section  51 , are connected to the wiring connection portions  89  of the three electrode members  87 A,  87 B and  87 C that are assembled to the contact-point unit  66 . 
     Further, as shown in  FIG. 42 , the contact-point unit  66  is provided with a substantially C-shaped electric contact-point member  96  which is formed of a metallic plate spring. The electric contact-point member  96  is connected to the outer-peripheral surface of the proximal end portion of the spring receiving member  64 . 
     The handle-unit-side electric path  95  is composed of the electrical contact member  96 , spring receiving member  64 , positioning pin  81  and rotation transmission member  71 . 
     A front end portion of the transducer unit  2  is detachably coupled to the contact-point unit  66 . As shown in  FIG. 52 , two wiring lines  101  and  102  for the ultrasonic transducer, two wiring lines  103  and  104  for high-frequency power and three wiring lines  105 ,  106  and  107 , which are connected to a wiring circuit board within the switch hold section  51 , are assembled in the single cable  9  at the rear end of the transducer unit  2 . Distal end portions of the two wiring lines  101  and  102  for the ultrasonic transducer are connected to the ultrasonic transducer  6 . A distal end portion of one wiring line  103  for high-frequency power is connected to the ultrasonic transducer  6 . 
     First to fourth electrically conductive plates  111  to  114  for electric connection are provided at the rear end of the transducer unit  2 . A distal end portion of the other wiring line  104  for high-frequency power is connected to the first conductive plate  111 . The three wiring lines  105 ,  106  and  107  are connected to the second to fourth conductive plates  112  to  114 . 
       FIG. 4  shows the internal structure of a front end portion of the transducer unit  2 . A connection cylindrical portion  121  is formed at the distal end portion of the transducer cover  7 . A C-ring  122  having a partly cut-out annular plate shape is mounted on the outer peripheral surface of the connection cylindrical body  121 . Three (first to third) cylindrical portions  123  to  125  with different outside diameters are projectingly provided on the inside of the connection cylindrical portion  121 . The first cylindrical portion  123  has a smallest outside diameter and has a greatest length of projection from the distal end of the connection cylindrical body  121 . The second cylindrical portion  124  has an outside diameter, which is greater than the outside diameter of the first cylindrical portion  123 , and has a length of projection from the distal end of the connection cylindrical body  121 , which is less than the length of projection of the first cylindrical portion  123 . The third cylindrical portion  125  has a greatest outside diameter and has a length of projection from the distal end of the connection cylindrical body  121 , which is less than the length of projection of the second cylindrical portion  124 . 
     A first cylindrical contact-point member  131  is mounted on the outer peripheral surface of the first cylindrical portion  123 . Similarly, a second cylindrical contact-point member  132  is mounted on the outer peripheral surface of the second cylindrical portion  124 , and a third cylindrical contact-point member  133  is mounted on the outer peripheral surface of the third cylindrical portion  125 . The second conductive plate  112  is connected to the first contact-point member  131 , the third conductive plate  113  is connected to the second contact-point member  132 , and the fourth conductive plate  114  is connected to the third contact-point member  133 . 
     A fourth contact-point member  134  is mounted on the inner peripheral surface of the first cylindrical body  123 . The fourth contact-point member  134  is connected to the first conductive plate  111 . 
     When the handle unit  4  and the transducer unit  2  are coupled, the contact-point unit  66  of the handle unit  4  and the front end portion of the transducer unit  2  are connected. At this time, the electrode member  87 A of the contact-point unit  66  and the first contact-point member  131  of the transducer unit  2  are connected. At the same time, the electrode member  87 B of the contact-point unit  66  and the second contact-point member  132  of the transducer unit  2  are connected, the electrode member  87 C of the contact-point unit  66  and the third contact-point member  133  of the transducer unit  2  are connected, and the C-shaped electric contact-point member  96  of the contact-point unit  66  and the fourth contact-point member  134  of the transducer unit  2  are connected. 
     Next, the operation of the present embodiment is described. The handpiece  1  of the ultrasonic therapeutic apparatus of the present embodiment, as shown in  FIG. 2 , comprises four units, namely, the transducer unit  2 , probe unit  3 , handle unit  4  and sheath unit  5 , which are detachable. When the handpiece  1  is used, the transducer unit  2  and the probe unit  3  are coupled. Thereby, the first high-frequency electric path  13 , which transmits a high-frequency current to the coupled body of the transducer unit  2  and probe unit  3 , is formed. 
     Subsequently, the handle unit  4  and the sheath unit  5  are coupled. When the handle unit  4  and sheath unit  5  are coupled, the connection tube body  34  is inserted in the rotation transmission member  71  of the handle unit  4  in the state in which the handle member  32  of the sheath unit  5  is held. When the sheath unit  5  and handle unit  4  are coupled, the engaging lever  43  on the handle unit  4  side is held in the state in which the engaging lever  43  rests on the inclined surface of the guide groove  41  of the handle member  32  of the sheath unit  5 , as shown in  FIG. 29  and  FIG. 30 . At this time, as shown in  FIG. 41A , the electrically conductive rubber ring  94   b  is held in the positional state in which the inner peripheral surface shape of the electrically conductive rubber ring  94   b  corresponds to the engaging portion  46  of the connection flange portion  33   c , that is, in the state in which the three corner portions  46   b  of the connection flange portion  33   c  correspond in position to the three corner portions  94   b   2  of the electrically conductive rubber ring  94   b . Accordingly, the connection flange portion  33   c  of the sheath unit  5  is inserted straight into the electrically conductive rubber ring  94   b . At the time of this insertion operation, as shown in  FIG. 41A , the conductive rubber ring  94   b  is held in the natural, non-compressed position. In this state, the sheath-unit-side electric path  40  and the handle-unit-side electric path  95  are not electrically connected. 
     Subsequently, following this insertion operation, the handle member  32  of the sheath unit  5  is rotated about the axis thereof, relative to the handle unit  4 . By this operation, as shown in  FIG. 31  and  FIG. 32 , the engaging lever  43  on the handle unit  4  side is inserted and engaged in the engaging recess portion  42  at one end portion of the guide groove  41 . At this time, as shown in  FIG. 41B , the electrically conductive rubber ring  94   b  is switched to the pressure contact position where the electrically conductive rubber ring  94   b  is put in pressure contact with the three corner portions  46   b  of the connection flange portion  33   c . Thereby, the sheath-unit-side electric path  40  and the handle-unit-side electric path  95  are electrically connected via the electrically conductive rubber ring  94   b . As a result, the second high-frequency electric path  97 , which transmits a high-frequency current, is formed in the coupled body of the sheath unit  5  and handle unit  4 . 
     When the sheath unit  5  is rotated about the axis thereof, the pair of engaging pins  45  on the handle unit  4  side are, at the same time, disengageably engaged in the engaging groove  44   a  at the terminal end portion of the guide groove  44  of the sheath unit  5 . Thereby, the spring receiving member  64  on the handle unit  4  side and the connection tube body  34  on the sheath unit  5  side are coupled via the engaging pins  45 . As a result, the operation force on the handle unit  4  side at the time when the movable handle  49  is closed relative to the stationary handle  47  can be transmitted to the driving pipe  19  of the jaw  17  on the sheath unit  5  side. This state is the coupled state between the sheath unit  5  and the handle unit  4 . 
     Thereafter, the coupled body of the sheath unit  5  and handle unit  4  and the coupled body of the ultrasonic transducer  6  and probe unit  3  are assembled as one body. In this assembling work, the contact-point unit  66  of the handle unit  4  is connected to the front end portion of the transducer unit  2 . At this time, the electrode member  87 A of the contact-point unit  66  and the first contact-point member  131  of the transducer unit  2  are connected. At the same time, the electrode member  87 B of the contact-point unit  66  and the second contact-point member  132  of the transducer unit  2  are connected, the electrode member  87 C of the contact-point unit  66  and the third contact-point member  133  of the transducer unit  2  are connected, and the C-shaped electric contact-point member  96  of the contact-point unit  66  and the fourth contact-point member  134  of the transducer unit  2  are connected. Thereby, the second high-frequency electric path  97  of the coupled body of the sheath unit  5  and handle unit  4  is connected to the wiring line  104  for high-frequency power within the cable  9 . Further, the three wiring lines  105 ,  106  and  107  within the cable  9  are connected to the wiring circuit board within the switch hold section  51 . This state is the completion state of the assembly of the handpiece  1 . 
     When the handpiece  1  is used, the movable handle  49  is opened/closed relative to the stationary handle  47 . The driving pipe  19  is axially moved in interlock with the operation of the movable handle  49 , and the jaw  17  is opened/closed, relative to the probe distal end portion  3   a  of the probe unit  3 , in interlock with the advancing/retreating movement of the driving pipe  19  in its axial direction. When the movable handle  49  is closed relative to the stationary handle  47 , the driving pipe  19  is pushed forward in interlock with the operation of the movable handle  49 . The jaw  17  is rotated and driven (to a closed position) in a direction toward the probe distal end portion  3   a  of the probe unit  3  in interlock with the pushing operation of the driving pipe  19 . By the rotation of the jaw  17  to its closed position, a living body tissue is held between the jaw  17  and the probe distal end portion  3   a  of the probe unit  3 . 
     In this state, one of the switch button  54  for coagulation and the switch button  55  for incision, which are provided on the stationary handle  47 , is selectively pressed. When the switch button  54  for coagulation is pressed, power is supplied to the first high-frequency electric path  13  for supplying a high-frequency current to the probe distal end portion  3   a  of the probe unit  3  and to the second high-frequency electric path  97  for supplying a high-frequency current to the jaw body  28  of the sheath unit  5 . Thereby, the two bipolar electrodes for high-frequency therapeutic treatment are constituted by the probe distal end portion  3   a  of the probe unit  3  and the jaw body  28  of the sheath unit  5 . By supplying a high-frequency current between the two bipolar electrodes which are constituted by the probe distal end portion  3   a  of the probe unit  3  and the jaw body  28  of the sheath unit  5 , bipolar high-frequency therapeutic treatment can be performed for the living body tissue between the jaw  17  and the probe distal end portion  3   a  of the probe unit  3 . 
     When the switch button  55  for incision is pressed, a driving current is supplied to the ultrasonic transducer  6  at the same time as the supply of high-frequency current, and the ultrasonic transducer  6  is driven. At this time, ultrasonic vibration from the ultrasonic transducer  6  is transmitted to the probe distal end portion  3   a  via the vibration transmission member  11 . Thereby, incision, resection, etc. of the living body tissue can be performed by making use of ultrasonic at the same time as the supply of high-frequency current. In the meantime, coagulation for the living body tissue can be performed by using ultrasonic. 
     When the movable handle  49  is opened relative to the stationary handle  47 , the driving pipe  19  is pulled to the proximal side in interlock with the opening operation of the removable handle  49 . The jaw  17  is driven (to an open position) in a direction away from the probe distal end portion  3   a  of the probe unit  3  in interlock with the pulling operation of the driving pipe  19 . 
     When the rotational operation knob  50  is rotated, the rotational movement of the rotation transmission member  71 , which rotates together with the rotational operation knob  50 , is transmitted to the spring receiving member  64  side via the pin  81 . Thereby, when the rotational operation knob  50  is rotated, the assembly unit of the rotation transmission member  71 , pin  81 , spring receiving member  64 , slider member  65  and coil spring  67  within the hold cylinder  48  is rotated together with the rotational operation knob  50  as one body about the axis thereof. Further, the rotational operation force of the rotational operation knob  50  is transmitted to the vibration transmission member  11  of the probe unit  3  via the tubular member  98  that rotates together with the spring receiving member  64  within the hold cylinder  48 . Thereby, the assembly unit within the hold cylinder  48  and the coupled body of the transducer unit  2  and probe unit  3  are rotated about the axis as one body. 
     At this time, the handle member  32  and guide cylindrical body  33  of the sheath unit  5  rotate together with the rotational operation knob  50 . Furthermore, the sheath  18  rotates together with the guide cylindrical body  33 , and the rotation of the guide cylindrical body  33  is transmitted to the connection tube body  34  and driving pipe  19  via the threaded pin  235 . Thus, the jaw  17  and probe distal end portion  3   a  of the therapeutic section  1 A are rotated about the axis at the same time together with the rotational operation knob  50 . 
     The following advantageous effects can be obtained by the above-described structure. Specifically, in the handpiece  1  of the ultrasonic therapeutic apparatus according to the present embodiment, the operating section  222 , which is disposed on the distal end side of the body section  221  of the driving pipe  19 , is formed of the U-shaped portion  226  having the U-shaped cross section. In addition, as shown in  FIG. 22 , the peripheral wall of the tubular distal end portion of the body section  221  includes the crescent-shaped arcuate cross-sectional portion  224 , which is formed by leaving a substantially crescent-shaped arcuate cross-sectional portion over a predetermined length in the axial direction, and cutting out the other portion. As shown in  FIG. 23 , the arcuate cross-sectional portion  224  includes the taper portion  225  with a tapered distal end portion, which is gradually tapered toward the distal end side. As shown in  FIG. 22  and  FIG. 25 , the U-shaped portion  226  is formed at the distal end of the taper portion  225 . Thus, there is no acute-angled part between the distal end portion of the driving pipe  19  and the operation section  222  having the connection section  223  that is connected to the jaw  17 . Therefore, when the jaw  17  is opened/closed relative to the probe distal end portion  3   a  via the driving pipe  19  in accordance with the operation of the operation handle  49 , no stress concentration occurs at the part between the distal end portion of the driving pipe  19  and the operation section  222 . As a result, stress concentration on the driving pipe  19 , which rotates the jaw  17 , can be prevented, and the operation force of the operation handle  49  can exactly be transmitted to the jaw. Thereby, the handpiece  1  can stably be operated. Moreover, a decrease in durability of the apparatus can be prevented. 
     In the present embodiment, the operating section  222  has the slit  227  extending in the axial direction of the sheath  18  in the distal end portion of the connecting surface  226   c . Thereby, when the jaw  17  is rotated via the coupling pin  217 , which is connected to the connection section  223  of the operation section  222 , in accordance with the axial advancing/retreating movement of the driving pipe  19 , the surrounding of the connection part between the connection section  223  of the operation section  222  and the coupling pin  217  can be made easily deformable. Thus, the rotating operation of the jaw  17  can smoothly be performed. 
     Further, the slit  227  has the terminal end portion  227   a  which is located at the position corresponding to the proximal end portion of the inclined surface of the connecting surface  226   c . Thereby, when the jaw  17  is rotated, the surrounding of the connection part between the connection section  223  of the operation section  222  and the coupling pin  217  can be made more easily deformable, and the rotating operation of the jaw  17  can smoothly be performed. 
     A second embodiment of the present invention will now be described with reference from  FIG. 53  to  FIG. 73 .  FIG. 53  schematically shows the entire structure of a handpiece  301  of an ultrasonic operating apparatus which is a surgical operating apparatus according to the second embodiment. The ultrasonic operating apparatus of the present embodiment is an ultrasonic coagulation/incision apparatus. This ultrasonic coagulation/incision apparatus can perform therapeutic treatment, such as incision, resection or coagulation, of a living body tissue by making use of ultrasonic, and can also perform therapeutic treatment by high-frequency waves. 
     The handpiece  301 , as shown in  FIG. 54 , comprises four units, namely, a transducer unit  302 , a probe unit (probe section)  303 , a handle unit (operation section)  304  and a sheath unit (sheath section)  305 . These units are detachably coupled. 
     As shown in  FIG. 56 , an ultrasonic transducer  306  for generating ultrasonic vibration by a piezoelectric element, which converts an electric current to ultrasonic vibration, is built in the transducer unit  302 . An outside of the ultrasonic transducer  306  is covered with a cylindrical transducer cover  307 . As shown in  FIG. 53 , a cable  309 , for supplying an electric current for generating ultrasonic vibration from a power supply device body  308 , extends from a rear end of the transducer unit  302 . 
     A proximal end portion of a horn  310 , which increases the amplitude of ultrasonic vibration, is coupled to a front end portion of the ultrasonic transducer  306 . A screw hole portion  310   a  for attachment of the probe is formed at a distal end portion of the horn  310 . 
       FIG. 57  shows the external appearance of the entire probe unit  303 . The probe unit  303  is designed such that the entire length thereof may become an integer number of times of half-wave length of the ultrasonic vibration. The probe unit  303  has a distal end portion and a proximal end portion, and includes a metallic rod-shaped vibration transmission member  311  having a long axis. A proximal end portion of the vibration transmission member  311  is provided with a screw portion  312  which is to be engaged with the screw hole portion  310   a  of the horn  310 . The screw portion  312  is engaged with the screw hole portion  310   a  of the horn  310  of the transducer unit  302 . Thereby, the probe unit  303  and the transducer unit  302  are assembled. At this time, a first high-frequency electric path  313 , through which a high-frequency current is transmitted, is formed in the coupled body of the ultrasonic transducer  306  and the probe unit  303 . 
     A probe distal end portion  303   a  is provided at a distal end portion of the vibration transmission member  311 . A first hold member is formed by the probe distal end portion  303   a . The probe distal end portion  303   a  is formed in a substantially J-shaped curved form. The probe distal end portion  303   a  constitutes a first electrode section which is one of bipolar electrodes. The cross-sectional area of the probe unit  303  is decreased in the axial direction at several nodes of vibration in the axial direction, so that an amplitude necessary for therapeutic treatment can be obtained at the probe distal end portion  303   a . Rubber rings  303   b , which are formed of elastic material in an annular shape, are attached to several positions of nodes of vibration along the axial direction of the probe unit  303 . The rubber rings  303   b  prevent interference between the probe unit  303  and the sheath unit  305 . 
     A flange portion  314  is provided at the position of the node of vibration on the most proximal end side in the axial direction of the probe unit  303 . Engaging recess portions (not shown) each having a key groove shape are formed on the outer peripheral surface of the flange portion  314 , for example, at three positions in the circumferential direction thereof. 
       FIG. 58  is a longitudinal cross-sectional view of the sheath unit  305 . The sheath unit  305  includes a sheath body  316 , which is formed of a circular cylindrical body, and a jaw  317  which is provided at a distal end of the sheath body  316 . The sheath body  316  includes a metallic outer sheath  318  which is an outer cylinder, and a metallic driving pipe (driving member)  319  which is an inner cylinder (inner sheath). The driving pipe  319  is axially movably inserted in the outer sheath  318 .  FIGS. 59A to 59C  and  FIG. 60  show the driving pipe  319 , and  FIGS. 61A to 61D  show the outer sheath  318 . 
     The outer peripheral surface of the outer sheath  318  is covered with an outer coating  318   a  which is formed of an insulating material such as a resin. An insulation tube  324 , which is formed of an insulating material, is provided on the inner peripheral side of the driving pipe  319 . 
     As shown in  FIG. 61A , a pair of left and right projection portions  325  are provided at a distal end portion of the outer sheath  318  so as to project in a forward direction of the outer sheath  318 . As shown in  FIG. 61B , a circular hole  325   a  is formed in each of the projection portions  325 . A proximal end portion of the jaw  317  is rotatably attached to the circular poles  325   a  of the projection portions  325  via boss portions  327  (to be described later). 
     Further, a notch portion  592  for smoothing the movement of the driving pipe  319  is formed on an upper side (in  FIG. 61B ) of the distal end portion of the outer sheath  318 . The notch portion  592  is formed to have a greater opening area than an opening portion  591  which is formed on a lower side (in  FIG. 61B ). As shown in  FIG. 65 , the notch portion  592  of the outer sheath  318  is covered with the outer coating  318   a  which is formed of an insulating material. When the probe unit  303  and the sheath unit  305  are assembled, the jaw  317  is positioned to be opposed to the probe distal end portion  303   a  of the probe unit  303 . 
       FIG. 67  shows that surface of the jaw  317 , which is opposed to the probe distal end portion  303   a . As shown in  FIG. 67 , the jaw  317  is formed in a substantially J-shaped curved form, which corresponds to the curved shape of the probe distal end portion  303   a , in accordance with the curved shape of the probe distal end portion  303   a  of the probe unit  303 . A therapeutic section  301 A of the handpiece  301  is constituted by the jaw  317  and the probe distal end portion  303   a.    
     The jaw  317  includes a metallic jaw body  501  (see  FIG. 62 ) which is an electrically conductive member, and a hold member  502  which is attached to the jaw body  501 . The hold member  502  is composed of an electrode member  503  (see  FIG. 63 ) for high-frequency therapeutic treatment, and a pad member  504  (see  FIG. 64 ) for ultrasonic therapeutic treatment. The electrode member  503  constitutes a second electrode section which is the other electrode of the bipolar electrodes. The pad member  504  is formed of an insulating material, for instance, a resin material such as polytetrafluoroethylene. 
     As shown in  FIGS. 67 and 68 , a groove portion  505 , which is formed in accordance with the curved shape of the probe distal end portion  303   a , is formed on the lower surface of the electrode member  503 . The pad member  504  is inserted and mounted in the groove portion  505 . 
     Inclined surfaces  505   a , which are configured to gradually increase the groove width toward a lower-side opening surface, as shown in  FIG. 68 , are formed on both side wall surfaces of the groove portion  505 . In addition, as shown in  FIG. 67 , tooth portions  503   b  for preventing a slip are formed on both side walls  503   a  of the groove portion  505  on the lower-side opening surface side. The tooth portions  503   b  form a slip-preventing section for preventing a slip of a clamped object between the probe distal end portion  303   a  and the jaw  317  when the jaw  317  and probe distal end portion  303   a  are engaged. A wall thickness T of the electrode member  503  is properly determined in consideration of the rigidity and coagulation performance. 
     Further, in the electrode member  503 , a notch portion  505   b  is formed at a bottom portion of the inclined surface  505   a  of the groove portion  505 . The notch portion  505   b  is formed in accordance with the curved shape of the probe distal end portion  303   a . A push portion  507  of the pad member  504  is disposed at the notch portion  505   b . The push portion  507  of the pad member  504  is a probe abutment member, on which the probe distal end portion  303   a  abuts, as shown in  FIG. 68 . 
     An alignment groove  507   a  is provided at a center of the push portion  507  of the pad member  504 . As shown in  FIG. 67 , the alignment groove  507   a  is formed over the entire length of the pad member  504  from a front end portion to a rear end portion of the push portion  507 . The probe distal end portion  303   a  is engaged in the alignment groove  507   a . In the state in which the probe distal end portion  303   a  is engaged in the alignment groove  507   a  of the push portion  507 , the probe distal end portion  303   a  is aligned and prevented from being displaced in the right-and-left direction (in  FIG. 68 ) relative to the electrode member  503 . Thereby, a clearance of a predetermined distance g 1  is secured between the probe distal end portion  303   a  and the opposed inclined surface  505   a  of the electrode member  503 , thus preventing contact between the inclined surfaces  505   a  of the electrode  503  and the probe distal end portion  303   a.    
     The probe distal end portion  303   a  is formed to have a cross-sectional shape shown in  FIG. 68 . Specifically, left and right inclined surfaces  303   a   1 , which are parallel to the left and right inclined surfaces  505   a  of the electrode member  503 , are formed on the upper surface side of the probe distal end portion  303   a . Left and right inclined surfaces  303   a   2 , which are in opposite directions to the left and right inclined surfaces  303   a   1 , are formed on the lower surface side of the probe distal end portion  303   a . A flat surface portion  303   a   3 , which is parallel to the alignment groove  507   a  of the push portion  507  of the pad member  504 , is formed between the left and right inclined surfaces  303   a   1  on the upper surface side of the probe distal end portion  303   a.    
     As shown in  FIG. 69 , projecting electrode portions  506  are formed on parts of the inclined surfaces  505   a  of the electrode member  503 . The projecting electrode portions  506  project toward the opposed surfaces of the probe distal end portion  303   a  in the state in which the flat surface portion  303   a   3  at the upper surface of the probe distal end portion  303   a  is engaged in the alignment groove  507   a  of the push portion  507 . Thereby, a gap g 2  between the projecting electrode portion  506  and the probe distal end portion  303   a  is formed by a narrow width part, which is narrower than the distance g 1  between those parts of the inclined surfaces  505   a  of the electrode member  503 , which are other than the projecting electrode portions  506 , and the probe distal end portion  303   a . In short, the gap g 2  of the narrow width part is formed to be g 2 &lt;g 1 . The projecting electrode portions  506  are disposed at a position where the probe distal end portion  303   a  does not easily suffer a stress due to ultrasonic vibration when a living body tissue is clamped between the inclined surfaces  505   a  of the electrode member  503  and the probe distal end portion  303   a.    
     As shown in  FIG. 64 , snap fit portions  507   b  are formed at a front end portion and a rear end portion of the push portion  507  of the pad member  504 . As shown in  FIG. 63 , snap fit engaging portions  503   c , which are disengageably engaged with the front and rear snap fit portions  507   b  of the pad member  504 , are formed on the electrode member  503 . 
     When the electrode member  503  and the pad member  504  are assembled, the snap fit portions  507   b  are engaged with the snap fit engaging portions  503   c  in the state in which the push portion  507  of the pad member  504  is inserted in the notch portion  505   b  of the groove portion  505  of the electrode member  503 . Thereby, the electrode member  503  and the pad member  504  are integrally assembled and the hold member  502  is formed. 
     A projection portion  510  for attachment is projectingly provided on that side of the hold member  502 , which is opposite to the surface thereof facing the probe distal end portion  303   a . A screw insertion hole  511  is formed in the projection portion  510 . 
     As shown in  FIG. 62 , a hold member engaging portion  512 , which engages the projection portion  510  of the hold member  502 , is provided on a distal end side of the jaw body  501 . The projection portion  510  of the hold member  502  is engaged with the hold member engaging portion  512 . Further, a screw hole  513  is formed in side wall portions of the hold member engaging portion  512 . As shown in  FIG. 65 , when the hold member engaging portion  512  of the jaw body  501  and the projection portion  510  of the hold member  502  are engaged, a fixing screw  514 , which is engaged in the screw hole  513  of the jaw body  501 , is inserted in the screw insertion hole  511  of the hold member  502 . In this state, the fixing screw  514  is fastened in the screw hole  513 , and thereby the hold member  502  is attached to the jaw body  501 . The electrode member  503  of the hold member  502  and the jaw body  501  are electrically connected via the fixing screw  514 . 
     A proximal end portion of the jaw body  501  has two-forked arm portions  515   a  and  515   b . The respective arm portions  515   a  and  515   b  have extension portions  515   a   1  and  515   b   1 , which extend obliquely downward from the position of a center line of the jaw body  501 . As shown in  FIG. 66 , the boss portions  327  are outwardly projectingly formed on outer surfaces of the extension portions  515   a   1  and  515   b   1 . The boss portions  327  of the extension portions  515   a   1  and  515   b   1  are inserted and engaged in the circular holes  525   a  of the left and right projection portions  325  at the distal end portion of the outer sheath  318 . Thereby, the jaw body  501  is rotatably attached by the boss portions  327  to the left and right projection portions  325  at the distal end portion of the outer sheath  318 . 
     An operation pin insertion hole  516  is formed in a proximal portion of each of the two arm portions  515   a  and  515   b . An operation pin  517  for coupling the jaw body  501  and the driving pipe  319  is inserted in the operation pin insertion holes  516 . The jaw body  501  and the driving pipe  319  are electrically connected via the operation pin  517 . 
     Thereby, the driving force of the driving pipe  319  is transmitted to the jaw  317  via the operation pin  517  by the advancing/retreating in the axial direction of the driving pipe  319 . Accordingly, the jaw  317  is rotated about the boss portions  327 . In this case, when the driving pipe  319  is pulled rearward, the jaw  317  is rotated about the boss portions  327  and driven (to an open position) in a direction away from the probe distal end portion  303   a . Conversely, when the driving pipe  319  is pushed forward, the jaw  317  is rotated about the boss portions  327  and driven (to a closed position) in a direction toward the probe distal end portion  303   a . A living body tissue is held between the jaw  317  and the probe distal end portion  303   a  of the probe unit  303  when the jaw  317  is rotated to the closed position. 
     The therapeutic section  301 A of the handpiece  301  is constituted by the jaw  317  and the probe distal end portion  303   a  of the probe unit  303 . The therapeutic section  301 A is configured to selectively perform a plurality of therapeutic functions, for example, two therapeutic functions (a first therapeutic function and a second therapeutic function) in this embodiment. For instance, the first therapeutic function is set to be a function of simultaneously outputting an ultrasonic therapeutic output and a high-frequency therapeutic output. The second therapeutic function is set to be a function of outputting only the high-frequency therapeutic output. 
     The first therapeutic function and second therapeutic function of the therapeutic section  301 A are not limited to the above-described configuration. For example, the first therapeutic function may be set to be a function of outputting an ultrasonic therapeutic output in a maximum output state, and the second therapeutic function may be set to be a function of outputting the ultrasonic therapeutic output in a preset arbitrary output state which is lower than the maximum output state. 
     As shown in  FIGS. 59A to 59C  and  FIG. 60 , the driving pipe  319  includes a tubular body section  521  and an operating section  522 . The body section  521  is inserted in the outer sheath  318  so as to be slidable in the axial direction of the outer sheath  318 . The operating section  522  is disposed on the distal end side of the body section  521 , and includes a connection section  523  which is connected to the jaw  317 . 
     The peripheral wall of a tubular distal end portion of the body section  521  includes a crescent-shaped arcuate cross-sectional portion  524 , which is formed by leaving a substantially crescent-shaped arcuate cross-sectional portion over a predetermined length along the axial direction, and cutting out the other portion. As shown in  FIG. 59A , the arcuate cross-sectional portion  524  includes a taper portion  525  with a tapered distal end side, which is processed to gradually taper toward the distal end side. As shown in  FIG. 59C , a U-shaped portion  526  having a U-shaped cross section is formed at a distal end of the taper portion  525 . The operating section  522  is constituted by the U-shaped portion  526 . 
     As shown in  FIG. 59C , the U-shaped portion  526  has two side surfaces  526   a  and  526   b , which are opposed to each other, and a connecting surface  526   c  which connects the two side surfaces  526   a  and  526   b . The connection section  523  is formed in each of the two side surfaces  526   a  and  526   b  of the U-shaped portion  526 . 
     As shown in  FIG. 60 , the insulation tube  324  includes a projection portion  528  which projects forward of the body section  521  of the driving pipe  319 . The projection portion  528  extends up to a rear end position of the U-shaped portion  526 . 
     Further, a proximal end portion of the insulation tube  324  extends to a proximal end side of the sheath body  316 . The driving pipe  319  and probe unit  303  are electrically insulated by the insulation tube  324 . 
       FIG. 70  shows a proximal end portion of the sheath body  316 . The proximal end portion of the outer sheath  318  includes a flare portion  529  which has a greater inside diameter than the other portion (see  FIG. 61D ). A proximal end portion of the driving pipe  319  extends more rearward than the flare portion  529  of the outer sheath  318 . 
     In addition, the proximal end portion of the sheath body  316  is provided with an attachment/detachment mechanism section  331  for attachment/detachment to/from the handle unit  304 . The attachment/detachment mechanism section  331  includes a circular cylindrical large-diameter knob member  332 , a guide cylindrical body (first tubular member)  333  which is formed of a metallic circular cylindrical body, and a circular cylindrical connection tube body (second tubular member)  334  which is formed of a resin material. 
     As shown in  FIG. 71 , the knob member  332  includes an annular knob body  332   a . As shown in  FIG. 72 , the knob body  332   a  includes two C-shaped members  332   a   1  and  332   a   2  each having a substantially C shape. The two C-shaped members  332   a   1  and  332   a   2  are formed of a resin material, and the annular knob body  332   a  is formed in the state to which both end portions of the two C-shaped members  332   a   1  and  332   a   2  are coupled. The two C-shaped members  332   a   1  and  332   a   2  are coupled by two fixing screws  332   b.    
     As shown in  FIG. 73 , engaging holes  601  are formed in inner peripheral surfaces of the two C-shaped members  332   a   1  and  332   a   2 . Head portions  335   a  of pins  335 , which restrict movement of internal parts, are engaged in the engaging holes  601 . Thereby, the positions of the pins  335  can be restricted. 
     The guide cylinder  333  includes a tubular body  333   a  which is fitted over the flare portion  529  of the proximal end portion of the outer sheath  318  and extends rearwards. The distal end portion of the tubular body  333   a  is provided with a large-diameter portion  333   b  which has a greater outside diameter than the other portion. The knob member  332  is fitted on the large-diameter portion  333   b . A connection flange portion  333   c , which projects outward, is formed on the outer peripheral surface of a rear end portion of the guide cylinder  333 . 
     Two pin insertion holes  333   b   1 , which extend in the radial direction, are formed in the large-diameter portion  333   b  of the tubular body  333   a . Shaft portion  335   b  of the pins  335  is inserted in the two pin insertion holes  333   b   1 . 
     Two pin insertion holes are similarly formed in the flare portion  529  of the outer sheath  318  at positions corresponding to the two pin insertion holes  333   b   1  of the tubular body  333   a . Shaft portions  335   b  of the pins  335  project inward through the two pin insertion holes  333   b   1  of the tuber body  333   a  and the two pin insertion holes of the outer sheath  318 . Thereby, the knob member  332 , the guide cylinder  333  and the flare portion  529  of the outer sheath  318  are integrally assembled by the pins  335  in the state in which the movement of the outer sheath  318  in the axial direction of the outer sheath  318  and the rotation thereof about the axis of the outer sheath  318  are restricted. 
     The connection tube body  334  is engaged in the guide cylinder  333  so as to be slidable in the axial direction of the outer sheath  318 . The proximal end portion of the driving pipe  319  is inserted and fitted in the inner peripheral surface of the distal end portion of the connection tube body  334 . 
     As shown in  FIG. 70 , a rotation restriction pin  535  is fixed on the proximal end portion of the driving pipe  319 . As shown in  FIG. 72 , the rotation restriction pin  535  includes a large-diameter head portion  535   a  and a small-diameter shaft portion  535   b . An engaging hole portion  602  for engagement with the head portion  535   a  of the rotation restriction pin  535  is formed in the connection tube body  334 . A pin engaging hole  603  for engagement with the shaft portion  535   b  of the rotation restriction pin  535  is formed in the proximal end portion of the driving pipe  319 . The driving pipe  319  and the connection tube body  334  are coupled via the rotation restriction pin  535 . At this time, the driving pipe  319  and the connection tube body  334  are integrally assembled in the state in which the movement of the driving pipe  319  and the connection tube body  334  in the axial direction of the driving pipe  319  and the rotation of thereof about the axis of the driving pipe  319  are restricted by the rotation restriction pin  535 . 
     The distal end portion of the connection tube body  334  is inserted into the inside of the flare portion  529  of the outer sheath  318  and extends to the vicinity of a stepped portion  529   a  between the outer sheath  318  and the flare portion  529 . 
     Seal means  530  for effecting sealing between the outer sheath  318  and the driving pipe  319  is provided between the flare portion  529  and the driving pipe  319 . The seal means  530  includes one backup ring  531  and one ring  533 . The O ring  533  is provided between the stepped portion  529   a  of the flare portion  529  and the backup ring  531  so as to be movable in the axial direction of the outer sheath  318 . The position of the backup ring  531  of the O ring  533  is restricted at the distal end portion of the connection tube body  334 . Further, the shape of the stepped portion  529   a  of the flare portion  529  is so used as to function as a front-side backup ring of the O ring  533 . Thereby, only one backup ring  531  may be provided as the backup ring of the O ring  533 . 
     The distal end portion of the connection tube body  334  has two slits  605  which extend along the axis of the driving pipe  319 . Inner end portions of the shaft portions  335   b  of the pins  335  are inserted and engaged in the slits  605 . Thereby, the movement in the rotational direction of the three parts, namely, the guide cylinder  333 , outer sheath  318  and connection tube body  334 , relative to the knob member  332 , can be restricted by the pin  335 . 
     An attachment/detachment section  336  for attachment/detachment to/from the handle unit  304  is disposed at the rear end portion of the knob member  332 . The attachment/detachment section  336  of the knob member  332  has a guide groove (not shown) with an inclined surface, and an engaging recess portion  342 . The guide groove is provided extending in a circumferential direction on the outer peripheral surface of the proximal end portion of the knob member  332 . In addition, the guide groove has a tapered inclined surface with an outside diameter gradually decreasing toward the rear end portion side of the knob member  332 . 
     The engaging recess portion  342  is formed at one end portion of the guide groove. The engaging recess portion  342  is formed of a recess portion having a smaller diameter than the inclined surface of the guide groove. The engaging recess portion  342  is configured such that an engaging lever  343  (to be described later) on the handle unit  304  side is disengageably engaged in the engaging recess portion  342 . 
     As shown in  FIG. 55 , the handle unit  304  mainly includes a stationary handle  347 , a hold cylinder  348 , a movable handle  349  and a rotational operation knob  350 . The hold cylinder  348  is provided on the upper part of the stationary handle  347 . A switch hold section  351  is provided between the stationary handle  347  and the hold cylinder  348 . 
     As shown in  FIG. 55 , the switch hold section  351  has a switch attachment surface on a front side thereof, to which a plurality of hand switches, for example, two hand switches (first switch  354  and second switch  355 ) in the present embodiment, are attached. The first switch  354  and second switch  355  are switches for selecting therapeutic functions of the therapeutic section  301 A of the handpiece  301 . 
     In the switch hold section  351 , the first switch  354  and second switch  355  are arranged in the up-and-down direction. The first switch  354  is disposed on an upper side of the switch hold section  351 , and is set to be a switch which selects a first therapeutic function that is frequently used among the plural therapeutic functions. The second switch  355  is disposed on a lower side of the switch hold section  351 , and is set to be a switch which selects another second therapeutic function of the plural therapeutic functions. For example, the first switch  354  is set to be a switch button for incision, and the second switch  355  is set to be a switch button for coagulation. 
     As shown in  FIG. 54 , the movable handle  349  has a substantially U-shaped arm section  356  at an upper part thereof. The U-shaped arm section  356  includes two arms  356   a  and  356   b . The movable handle  349  is assembled to the hold cylinder  348  in the state in which the hold cylinder  348  is inserted between the two arms  356   a  and  356   b.    
     Each of the arms  356   a  and  356   b  has a support pin  357  and an operation pin  358 . A pin receiving hole portion (not shown) and a window portion (not shown) are formed in each of both side portions of the hold cylinder  348 . The support pin  357  of each arm  356   a ,  356   b  is inserted in the pin receiving hole portion of the hold cylinder  348 . Thereby, an upper end portion of the movable handle  349  is rotatably supported on the hold cylinder  348  via the support pins  357 . 
     Ring-shaped finger hook portions  361  and  362  are provided on lower end portions of the stationary handle  347  and movable handle  349 , respectively. By hooking the fingers on the finger hook portions  361  and  362  and holding them, the movable handle  349  rotates via the support pins  357  and the movable handle  349  is opened/closed relative to the stationary handle  347 . 
     The operation pins  358  of the movable handle  349  extend into the hold cylinder  348  through the window portions of the hold cylinder  348 . An operation force transmission mechanism (not shown), which transmits an operation force of the movable handle  349  to the driving pipe  319  of the jaw  317 , is provided inside the hold cylinder  348 . 
     If the movable handle  349  is held and the movable handle  349  is closed relative to the stationary handle  347 , the operation pins  358  rotate about the support pins  357  in accordance with the rotational operation of the movable handle  349  at this time. A slider member (not shown) of the operation force transmission mechanism, which is in interlock with the rotation of the support pins  357 , moves forward in the axial direction. At this time, the operation force of the movable handle  349  is transmitted to the connection tube body  334  of the sheath unit  305  via the operation force transmission mechanism, and the driving pipe  319  of the jaw  317  moves forward. Thereby, the jaw body  501  of the jaw  317  rotates via the boss portions  327 . 
     Further, when a living body tissue is clamped between the hold member  502  of the jaw  317  and the probe distal end portion  303   a  of the probe unit  303  by this operation, the hold member  502  rotates over a certain angle about the fixing screw  514  in accordance with the bending of the probe distal end portion  303   a  so that force uniformly acts over the entire length of the hold member  502 . In this state, ultrasonic is output and a living body tissue, such as a blood vessel, can be coagulated or incised. 
     The rotational operation knob  350  is fitted and fixed on the front end portion of the hold cylinder  348 . The engaging lever  343  and an operation button  376  for operating the engaging lever  343  in such a direction as to release engagement of the engaging lever  343  are provided at the front end portion of the rotational operation knob  350 . 
     Next, the operation of the present embodiment is described. The handpiece  301  of the ultrasonic operating apparatus of the present embodiment, as shown in  FIG. 54 , comprises four units, namely, the transducer unit  302 , probe unit  303 , handle unit  304  and sheath unit  305 , which are detachable. When the handpiece  301  is used, the transducer unit  302  and the probe unit  303  are coupled. Thereby, the first high-frequency electric path  313 , which transmits a high-frequency current to the coupled body of the transducer unit  302  and probe unit  303 , is formed. 
     Subsequently, the handle unit  304  and the sheath unit  305  are coupled. When the handle unit  304  and sheath unit  305  are coupled, the connection tube body  334  is inserted in the hold cylinder  348  of the handle unit  304  in the state in which the knob member  332  of the sheath unit  305  is held. After this insertion operation, the knob member  332  of the sheath unit  305  is rotated about the axis, relative to the handle unit  304 . By this operation, the engaging lever  343  on the handle unit  304  side is inserted and engaged in the engaging recess portion  342  of the knob member  332 . Thereby, the sheath-unit-side electric path (not shown) and the handle-unit-side electric path are electrically connected. As a result, the second high-frequency electric path, which transmits a high-frequency current, is formed in the coupled body of the sheath unit  305  and handle unit  304 . 
     When the sheath unit  305  is rotated about the axis thereof, the operation force on the handle unit  304  side at the time when the movable handle  349  is closed relative to the stationary handle  347  can be transmitted, at the same time, to the driving pipe  319  of the jaw  317  on the sheath unit  305  side. This state is the coupled state between the sheath unit  305  and the handle unit  304 . 
     Thereafter, the coupled body of the sheath unit  305  and handle unit  304  and the coupled body of the ultrasonic transducer  306  and probe unit  303  are assembled as one body. In this assembling work, the second high-frequency electric path of the coupled body of the sheath unit  305  and handle unit  304  is connected to the wiring line for high-frequency power within the cable  309 . 
     When the handpiece  301  is used, the movable handle  349  is opened/closed relative to the stationary handle  347 . The driving pipe  319  is axially moved in interlock with the operation of the movable handle  349 , and the jaw  317  is opened/closed, relative to the probe distal end portion  303   a  of the probe unit  303 , in interlock with the advancing/retreating movement of the driving pipe  319  in its axial direction. 
     When the movable handle  349  is closed relative to the stationary handle  347 , the driving pipe  319  is pushed forward in interlock with the operation of the movable handle  349 . The jaw  317  is rotated and driven (to a closed position) in a direction toward the probe distal end portion  303   a  of the probe unit  303  in interlock with the pushing operation of the driving pipe  319 . By the rotation of the jaw  317  to its closed position, a living body tissue is held between the jaw  317  and the probe distal end portion  303   a  of the probe unit  303 . 
     In this state, one of the switch button  54  for incision and the switch button  55  for coagulation, which are provided on the stationary handle  347 , is selectively pressed. When the switch button  55  for coagulation is pressed, power is supplied to the first high-frequency electric path  313  for supplying a high-frequency current to the probe distal end portion  303   a  of the probe unit  303  and to the second high-frequency electric path for supplying a high-frequency current to the jaw body  28  of the sheath unit  305 . Thereby, the two bipolar electrodes for high-frequency therapeutic treatment are constituted by the probe distal end portion  303   a  of the probe unit  303  and the jaw body  28  of the sheath unit  305 . By supplying a high-frequency current between the two bipolar electrodes which are constituted by the probe distal end portion  303   a  of the probe unit  303  and the jaw body  28  of the sheath unit  305 , bipolar high-frequency therapeutic treatment can be performed on the living body tissue between the jaw  317  and the probe distal end portion  303   a  of the probe unit  303 . 
     When the switch button  54  for incision is pressed, a driving current is supplied to the ultrasonic transducer  306  at the same time as the supply of high-frequency current, and the ultrasonic transducer  306  is driven. At this time, ultrasonic vibration from the ultrasonic transducer  306  is transmitted to the probe distal end portion  303   a  via the vibration transmission member  311 . Thereby, incision, resection, etc. of the living body tissue can be performed by making use of ultrasonic wave at the same time as the supply of high-frequency current. In the meantime, coagulation for the living body tissue can be performed by using ultrasonic wave. 
     When the movable handle  349  is opened relative to the stationary handle  347 , the driving pipe  319  is pulled to the proximal side in interlock with the opening operation of the movable handle  349 . The jaw  317  is driven (to an open position) in a direction away from the probe distal end portion  303   a  of the probe unit  303  in interlock with the pulling operation of the driving pipe  319 . 
     When the rotational operation knob  350  is rotated, the assembly unit within the hold cylinder  348  is rotated together with the rotational operation knob  350  as one body about the axis thereof. Further, the rotational operation force of the rotational operation knob  350  is transmitted to the vibration transmission member  311  of the probe unit  303 . Thereby, the assembly unit within the hold cylinder  348  and the coupled body of the transducer unit  302  and probe unit  303  are rotated about the axis as one body. 
     At this time, the knob member  332  and guide cylindrical body  333  of the sheath unit  305  rotate together with the rotational operation knob  350 . Furthermore, the outer sheath  318  rotates together with the guide cylindrical body  333 , and the rotation of the guide cylindrical body  333  is transmitted to the connection tube body  334  and driving pipe  319  via the rotation restriction pin  535 . Thus, the jaw  317  and probe distal end portion  303   a  of the therapeutic section  301 A are rotated about the axis at the same time together with the rotational operation knob  350 . 
     The following advantageous effects can be obtained with the above-described structure. Specifically, in the handpiece  301  of the ultrasonic operating apparatus of the present embodiment, the projecting electrode portions  506  are formed on the electrode member  503  of the jaw  317  of the therapeutic section  301 A. The projecting electrode portions  506  project from the inclined surfaces  505   a  of the electrode member  503  toward the opposed surfaces of the probe distal end portion  303   a  in the state in which the probe distal end portion  303   a  is engaged in the alignment groove  507   a  of the push portion  507 . Thereby, the gap g 2  between the projecting electrode portion  506  and the probe distal end portion  303   a  is formed by the narrow width part, which is narrower than the distance g 1  between those parts of the inclined surfaces  505   a  of the electrode member  503 , which are other than the projecting electrode portions  506 , and the probe distal end portion  303   a . The projecting electrode portions  506  are formed at a position where the probe distal end portion  303   a  does not easily suffer a stress when a living body tissue is clamped between the inclined surfaces  505   a  of the electrode member  503  and the probe distal end portion  303   a . For example, the projecting electrode portions  506  are disposed at a position, such as a distal end side position of the probe distal end portion  303   a , which is away from a proximal end side position of the curved shape (indicated by the arrow P in  FIG. 69 ) where a stress due to ultrasonic vibration tends to concentrate. 
     Thus, when the pad member  504  is worn due to ultrasonic therapeutic treatment, the parts of the projecting electrode portions  506  can be first put in contact with the probe distal end portion  303   a , and a spark can be occurred. As a result, the position of occurrence of a spark (the position where a crack occurs in the probe distal end portion  303   a ) can be controlled. Thereby, it becomes possible to surely prevent the occurrence of a spark at the proximal end side position of the curved shape (indicated by the arrow P in  FIG. 69 ) where a stress due to ultrasonic vibration tends to concentrate. Therefore, a crack does not easily occur in the probe distal end portion  303   a , and the durability can be improved. Moreover, in case a crack occurs in the probe distal end portion  303   a , the crack can exactly be detected by the probe breakage detection section of the apparatus body. 
     The probe breakage detection section of the apparatus body is constituted as follows. Specifically, the probe breakage detection section detects the frequency of ultrasonic vibration. In general, the frequency of the probe+transducer is designed at a predetermined preset value, e.g. 47±1 kHz. As long as the frequency of ultrasonic vibration, which is detected by the probe breakage detection section, falls within the above range, ultrasonic vibration can be output. However, if a crack occurs in the probe, the frequency increases (the wavelength decreases), and the frequency falls out of the above range. Consequently, the body stops the output. However, if a crack occurs at a distal end side position of the curved shape of the probe distal end portion, the degree of increase of the frequency of ultrasonic vibration is small, and it becomes difficult for the probe breakage detection section to detect the broken state of the probe. In the present embodiment, as described above, the position where a spark occurs (the position where a crack occurs in the probe distal end portion  303   a ) can be controlled. Therefore, it is possible to surely prevent the occurrence of a spark at the distal end side position of the curved shape of the probe distal end portion. As a result, the safety can be ensured. 
     Besides, in the present embodiment, the alignment groove  507   a  is provided at a center of the push portion  507  of the pad member  504 . Thus, the probe distal end portion  303   a  is engaged and fitted in the alignment groove  507   a . By engaging the probe distal end portion  303   a  in the alignment groove  507   a  of the push portion  507 , the probe distal end portion  303   a  can be prevented from being displaced in the right-and-left direction (in  FIG. 68 ) relative to the electrode member  503 . As a result, the clearance between the electrode member  503  and the probe distal end portion  303   a  can be exactly controlled. 
     Further, in the present embodiment, the boss portions  327  are outwardly projectingly formed on the arm portions  515   a  and  515   b  at the proximal end portion of the jaw body  501 . The boss portions  327  are inserted and engaged in the circular holes  525   a  of the left and right projection portions  325  at the distal end portion of the outer sheath  318 . Thereby, the jaw body  501  is rotatably attached by the boss portions  327  to the left and right projection portions  325  at the distal end portion of the outer sheath  318 . Therefore, the number of parts can be reduced, compared to the case in which the proximal end portion of the jaw body  501  is connected to the distal end portion of the outer sheath  318  by separate parts such as pins. Thereby, the work of assembly between the jaw body  501  and the distal end portion of the outer sheath  318  can be facilitated. 
     In the present embodiment, as shown in  FIG. 64 , the snap fit portions  507   b  are formed at the front end portion and the rear end portion of the push portion  507  of the pad member  504 . As shown in  FIG. 63 , the snap fit engaging portions  503   c  are formed on the electrode member  503 . When the electrode member  503  and the pad member  504  are assembled, the snap fit portions  507   b  are engaged with the snap fit engaging portions  503   c . Thereby, the electrode member  503  and the pad member  504  are integrally assembled. Therefore, the work of assembly between the electrode member  503  and the pad member  504  can be made easier than in the prior art. 
     In the present embodiment, as shown in  FIG. 72 , in the knob member  332  at the proximal end portion of the sheath body  316 , the two C-shaped members  332   a   1  and  332   a   2  each having a substantially C shape are coupled by the two fixing screws  332   b , and thus the annular knob body  332   a  is formed as shown in  FIG. 71 . Further, the engaging holes  601  are formed in inner peripheral surfaces of the two C-shaped members  332   a   1  and  332   a   2 . The head portions  335   a  of the pins  335 , which restrict movement of internal parts, are engaged in the engaging holes  601 . Thereby, the positions of the pins  335  can be restricted. Therefore, the number of internal parts assembled in the knob member  332  can be made less than in the prior art, and the assembly can be made easier. 
     In the present embodiment, since the position of the backup ring  531  of the O ring  533  is restricted at the distal end portion of the connection tube body  334 , there is no need to provide other parts for restricting the position of the backup ring  531 . Therefore, the number of parts can be reduced and the assembly can be made easier. 
     In the present embodiment, the movement of the three parts, namely, the knob member  332 , the guide cylinder  333  and the flare portion  529  of the outer sheath  318  in the axial direction of the outer sheath  318  and the movement thereof about the axis of the outer sheath  318  are restricted by the pins  335 . Thereby, compared to the prior art, the number of parts can be reduced and the assembly can be made easier. 
     In the present embodiment, the stepped portion  529   a  between the outer sheath  318  and the flare portion  529  can be made to serve also as a front-side backup ring of the O ring  533 . Thus, it should suffice to provide only one backup ring  531  on the rear side of the O ring  533 . Thereby, compared to the case in which backup rings are provided in front of and behind the O ring  533 , the number of parts can be reduced and the assembly can be made easier. 
     In the present embodiment, the diameter of the head portion  535   a  of the rotation restriction pin  535 , which couples between the driving pipe  319  and connection tube body  334  and restricts the axial movement of the driving pipe  319  and the rotation of the driving pipe  319  about its axis, is increased. Thereby, swinging of the head portion  535   a  of the rotation restriction pin  535  can be prevented. 
     Further, in the present embodiment, the notch portion  592  for smoothing the movement of the driving pipe  319  is formed on the upper side (in  FIG. 61B ) of the distal end portion of the outer sheath  318 . When the jaw  317  is rotated, the coupling portion between the connection section  523  of the U-shaped portion  526  of the driving pipe  319  and the operation pin  517  of the jaw  317  makes arcuate movement. Consequently, the U-shaped portion  526  of the driving pipe  319  moves up and down. At this time, when the U-shaped portion  526  of the driving pipe  319  moves upward, the notch portion  592  at the distal end portion of the outer sheath  318  can prevent contact between the outer sheath  318  and the driving pipe  319 . Therefore, when the U-shaped portion  526  of the driving pipe  319  moves upward, it is possible to prevent occurrence of frictional force due to contact between the outer sheath  318  and the driving pipe  319 , which leads to non-smooth sliding movement. As a result, the rotational operation of the jaw  317  can smoothly be performed. 
     In the present embodiment, there is no need to form a slit in the U-shaped portion  526  of the driving pipe  319 . Accordingly, a decrease in strength of the U-shaped portion  526  of the driving pipe  319  can be prevented. 
     In the present embodiment, as shown in  FIG. 65 , the notch portion  592  of the outer sheath  318  is covered with the outer coating  318   a  which is formed of an insulating material. Thus, it is possible to prevent the notch portion  592  of the outer sheath  318  from being caught by, for instance, a trocar. 
     Needless to say, the present invention is not limited to the above-described embodiments, and various modifications may be made without departing from the spirit of the invention. 
     Additional advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its 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.