Abstract:
An ultrasonic vibration apparatus includes a vibrator including at least two vibration elements, at least three electrode portions, a bridging portion and an anti-vibration portion. The vibration elements are configured to generate ultrasonic vibration. The vibration elements and the electrode portions are alternately arranged side by side in a vibrating direction. The electrode portions include at least two first electrode portions and at least one second electrode portion alternately arranged in the vibrating direction. The vibrator integrally vibrates ultrasonically in the vibrating direction when the driving voltage is applied to the first and second electrode portions. The bridging portion couples and electrically connects the first electrode portions with each other. The anti-vibration portion is configured to suppress vibration of the bridging portion in any other direction-except the vibration direction and configured to cover the entire vibrator including the bridging portion.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
       [0001]    This application is a divisional of U.S. Application Ser. No. 12/132,041, filed Jun. 3, 2008, by Yuji HIRAI, et al., entitled ULTRASONIC VIBRATION APPARATUS, the contents of which are incorporated by this reference. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to an ultrasonic vibration apparatus including a vibrator, the vibrator includes vibration elements and electrode portions alternately arranged side by side in a vibration direction, and the electrode portions having the same pole are sequentially coupled and electrically connected with each other by a bridging portion. 
         [0004]    2. Description of the Related Art 
         [0005]    Each of Jpn. Pat. Appln. KOKAI Publication No. 4-156983, a specification of U.S. Pat. No. 6,278,218, and a specification of U.S. Pat. No. 5,989,275 discloses a bolted Langevin type vibrator. In the bolted Langevin type vibrator, piezoelectric elements and electrode plates are alternately arranged side by side in a longitudinal direction. The electrode plate includes negative electrode plates and positive electrode plates alternately arranged in the longitudinal direction. The electrode plates having the same pole are sequentially coupled and electrically connected with each other by bridging portions. When driving voltage is applied to the negative electrode plates and the positive electrode plates, the driving voltage is applied to the piezoelectric elements to generate ultrasonic vibration and so the entire vibrator vibrates ultrasonically in the longitudinal direction. 
       BRIEF SUMMARY OF THE INVENTION 
       [0006]    In an aspect of the present invention, an ultrasonic vibration apparatus includes a vibrator, wherein the vibrator includes: at least two vibration elements to generate ultrasonic vibration when a driving voltage is applied to the vibration elements; at least three electrode portions wherein the vibration elements and the electrode portions is alternately arranged side by side in a vibrating direction, at least the three electrode portions includes at least two first electrode portions and at least one Ser. No. 12/132,041, filed Jun. 3, 2008, by Yuji HIRAI, et al., entitled ULTRASONIC VIBRATION APPARATUS cond electrode portion alternately arranged in the vibrating direction, the vibrator integrally vibrates ultrasonically in the vibrating direction when the driving voltage is applied to the first electrode portions and the second electrode portion; and a bridging portion coupling and electrically connecting two first electrode portions of at least the two first electrode portions with each other, and the ultrasonic vibration apparatus further includes an anti-vibration portion to suppress vibration of the bridging portion in any other direction except the vibrating direction. 
     
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING 
         [0007]    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. 
           [0008]      FIG. 1  is a perspective view showing an ultrasonic accessory according to a first embodiment of the present invention; 
           [0009]      FIG. 2  is a partial cross-sectional side view showing a vibrator according to the first embodiment of the present invention; 
           [0010]      FIG. 3  is an exploded perspective view showing a vibration generating portion according to the first embodiment of the present invention; 
           [0011]      FIG. 4  is a side view showing a vibrator according to a second embodiment of the present invention; 
           [0012]      FIG. 5  is a partial cross-sectional side view showing a vibrator according to a third embodiment of the present invention; 
           [0013]      FIG. 6  is a partial cross-sectional side view showing a vibrator according to a fourth embodiment of the present invention; 
           [0014]      FIG. 7  is a cross-sectional view showing a vibration generating portion according to a fifth embodiment of the present invention; 
           [0015]      FIG. 8  is a development showing an electrode member according to a sixth embodiment of the present invention; 
           [0016]      FIG. 9  is a side view showing a vibrator according to a seventh embodiment of the present invention; 
           [0017]      FIG. 10  is a side view showing a vibrator according to a reference embodiment according to the present invention; 
           [0018]      FIG. 11  is a development showing an electrode member according to the reference embodiment of the present invention; and 
           [0019]      FIG. 12  is a side view showing the electrode member according to the reference embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0020]    Each embodiment according to the present invention will now be explained hereinafter with reference to the drawings. 
         [0021]      FIGS. 1 to 3  show a first embodiment of the present invention. 
         [0022]    An outline structure of an ultrasonic accessory will now be explained with reference to  FIG. 1 . 
         [0023]    The ultrasonic accessory includes an elongated sheath unit  12 . A handle unit  14  to be held and operated by an operator is coupled with a proximal end side of the sheath unit  12 . A pair of handles  16  openable and closable is arranged in the handle unit  14 . A vibrator unit  18  is coupled with a proximal end side of the handle unit  14 . A vibrator to generate ultrasonic vibration is housed in the vibrator unit  18 . An electric cord  22  is extended from the vibrator unit  18  and connected with a main body. A driving voltage is supplied to the vibrator from the main body through the electric cord  22  and so ultrasonic vibration is generated in the vibrator. A proximal end portion of an elongated probe  24  to transmit the ultrasonic vibration is coupled with a distal end portion of the vibrator. The probe  24  is inserted through the handle unit  14  and the sheath unit  12  and protruded from a distal end portion of the sheath unit  12 . Further, a jaw  26  is arranged at the distal end portion of the sheath unit  12 . When the pair of handles  16  in the handle unit  14  is opened or closed, the jaw  26  is opened or closed with respect to a distal end portion of the probe  24 . When the distal end portion of the probe  24  and the jaw  26  grasp a living tissue and the probe  24  is vibrated ultrasonically, the living tissue is treated. 
         [0024]    The vibrator  20  will now be explained in detail with reference to  FIGS. 2 and 3 . 
         [0025]    A vibration generating portion  28  to generate the ultrasonic vibration is formed on a proximal end side of the vibrator  20 . In the vibration generating portion  28 , piezoelectric elements  30  each having a thick disk shape as vibration elements and electrode plates  32   a  and  32   b  each having a thin disk shape as electrode portions are coaxially alternately arranged side by side in a longitudinal direction forming a longitudinal direction of the ultrasonic accessory. As the electrode plates  32   a  and  32   b , negative electrode plates  32   a  and positive electrode plates  32   b  are alternately arranged in the longitudinal direction. The electrode plates  32   a  and  32   b  having the same pole and adjacent to each other are coupled and electrically connected with each other by a bridging portion  34   a  or  34   b . That is, the electrode plates  32   a  and  32   b  are sequentially coupled with each other in the longitudinal direction by the bridging portions  34   a  and  34   b . Each of the bridging portions  34   a  and  34   b  is formed of extended portions on both ends outwardly extended in a radial direction from both the electrode plates  32   a  and  32   b  and an intermediate coupling portion extended in the longitudinal direction to couple both the extended portions. The bridging portions  34   a  and  34   b  having the same pole are arranged in the longitudinal direction to be sequentially shifted 180° along a circumferential direction, and the negative and positive bridging portions  34   a  and  34   b  are arranged in the longitudinal direction to be sequentially shifted 90° along the circumferential direction. Lead portions  36   a  and  36   b  are extended from the negative electrode plate  32   a  and the positive electrode plate  32   b  on the most proximal end, respectively, and the electrode plates  32   a  and  32   b  are electrically connected with the lead portions  36   a  and  36   b , respectively. A voltage cable is connected with each of the lead portions  36   a  and  36   b  and led to the electric cord  22 . In this embodiment, the electrode plates  32   a  and  32   b , the bridging portions  34   a  and  34   b , and the lead portions  36   a  and  36   b  having the same pole are formed of integral electrode members  40   a  and  40   b  processed through bending processing. A horn  42  is arranged on a distal end side of the vibration generating portion  28 . The horn  42  forms a vibration transmitting portion  29  to amplify and transmit the ultrasonic vibration, has a substantially columnar shape, and is extended in the longitudinal direction. A flange portion  43  is formed at a proximal end portion of the horn  42 , and a bolt is protruded from a proximal end face of the flange portion  43  toward the proximal end side. The bolt is inserted through central openings of the electrode plates  32   a  and  32   b  and the piezoelectric elements  30 , and a backboard  44  is screwed into a terminal end portion of the bolt. The backboard  44  is screwed into the bolt and so the piezoelectric elements  30  and the electrode plates  32   a  and  32   b  are held between the proximal end face of the horn  42  and a distal end face of the backboard  44 . 
         [0026]    A tubular fitted-outside member  46  as an anti-vibration member is fitted on outside of the vibration generating portion  28  of the vibrator  20 . The fitted-outside member  46  has insulation properties and relatively small elastic properties and is tend to contract inwardly in the radial direction. Furthermore, the fitted-outside member  46  covers the bridging portions  34   a  and  34   b  and gives the bridging portions  34   a  and  34   b  a radially inward load. In this embodiment, a heat-shrinkable tube is used as the fitted-outside member  46 . 
         [0027]    When vibrating the vibrator  20  ultrasonically, a driving voltage is applied to the negative and positive electrode member  40   a  and  40   b  through the negative and positive voltage cables. The driving voltage is applied to the respective piezoelectric elements  30  between the negative electrode plates  32   a  and the positive electrode plates  32   b , the ultrasonic vibration is generated in the respective piezoelectric elements  30 , and the entire vibrator  20  vibrates ultrasonically in the longitudinal direction. Therefore, the bridging portions  34   a  and  34   b  also vibrates ultrasonically in the longitudinal direction. Here, since the fitted-outside member  46  gives the bridging portions  34   a  and  34   b  the radially inward load and the fitted-outside member  46  prevents the bridging portions  34   a  and  34   b  from vibrating in any other direction except the longitudinal direction, occurrence of the vibration in any other direction except the longitudinal direction in the bridging portions  34   a  and  34   b  is suppressed. As a result, fatigue of the bridging portions  34   a  and  34   b  is reduced, and so fracture of the bridging portions  34   a  and  34   b  is prevented. 
         [0028]    It is to be noted that, in the vibrator  20  in this embodiment, the horn  42  and the backboard  44  are electrically connected with each other through the bolt inserted through the central openings of the piezoelectric elements  30  and the electrode plates  32   a  and  32   b . That is, the negative electrode plate  32   a  at the most proximal end, the backboard  44 , the bolt, and the horn  42  are electrically connected with each other. Therefore, in a case where the flange portion  43  at the proximal end portion of the horn  42  functions as the negative electrode plate as the electrode portion, the negative electrode plate  32   a  adjacent to the flange portion  43  and the bridging portion  34   a  coupling the former negative electrode plate  32   a  with the negative electrode plate  32   a  adjacent to the former negative electrode plate  32   a  can be eliminated. 
         [0029]      FIG. 4  shows a second embodiment of the present invention. 
         [0030]    In the vibrator  20  according to this embodiment, buried members  48  as the anti-vibration members are embedded between the bridging portions  34   a  and  34   b , and, the piezoelectric elements  30  and the electrode plates  32   a  and  32   b . The buried member  48  has insulating properties and elastic properties. In this embodiment, the buried member  48  is formed of a silicone rubber. When the vibrator  20  vibrates ultrasonically, the buried members  48  interfere with vibration in any other direction except the longitudinal direction of the bridging portions  34   a  and  34   b , and so occurrence of the vibration in any other direction except the longitudinal direction in the bridging portions  34   a  and  34   b  is suppressed. 
         [0031]      FIG. 5  shows a third embodiment according to the present invention. 
         [0032]    In the vibrator unit  18 , the vibrator  20  is housed in a housing  50  as a housing portion, and the vibration generating portion  28  of the vibrator  20  is arranged in an airtight inner space  52 . An interposed member  54  as the anti-vibration member is interposed between the housing  50  and the bridging portions  34   a  and  34   b . The interposed member  54  has insulating properties and elastic properties, is compressed between the housing  50  and the bridging portions  34   a  and  34   b , and gives the bridging portions  34   a  and  34   b  a radially inward load. In this embodiment, a rubber plate is used as the interposed member  54 . When the vibrator  20  vibrates ultrasonically, the interposed member  54  gives the bridging portions  34   a  and  34   b  the radially inward load, and so the interposed member  54  prevents the bridging portions  34   a  and  34   b  from vibrating in any other direction except the longitudinal direction, and the interposed member  54  interferes with the vibration of the bridging portions  34   a  and  34   b  in any other direction except the longitudinal direction, and so occurrence of the vibration of the bridging portions  34   a  and  34   b  in any other direction other except the longitudinal direction is suppressed. 
         [0033]      FIG. 6  shows a fourth embodiment according to the present invention. 
         [0034]    In this embodiment, the inner space  52  where the vibration generating portion  28  is arranged is filled with a filling liquid  56  as an anti-vibration solution. The filling liquid  56  has insulating properties and relatively high viscosity. In this embodiment, a silicone oil is used as the filling liquid  56 . When the vibrator  20  vibrates ultrasonically, the filling liquid  56  interferes with vibration of the bridging portions  34   a  and  34   b  in any other direction except the longitudinal direction, and so occurrence of the vibration in any other direction except the longitudinal direction in the bridging portions  34   a  and  34   b  is suppressed. Moreover, in a case where the inner space  52  is not filled with the filling liquid  56 , when the ultrasonic accessory is subjected to, e.g., autoclave sterilization using high-temperature and pressure vapor, vapor may enter the inner space  52  of the housing  50 , and droplets may adhere to a surface of the vibration generating portion  28 , and so an electrostatic capacity of the vibration generating portion  28  may vary, and vibration characteristics of the vibrator  20  may change. In this embodiment, since the inner space  52  is filled with the insulative filling liquid  56 , vapor is prevented from entering the inner space, and so a change in vibration characteristics of the vibrator  20  is prevented. 
         [0035]      FIG. 7  shows a fifth embodiment according to the present invention. 
         [0036]    In this embodiment, each of the electrode members  40   a  and  40   b  is formed of a soft flexible substrate. In this embodiment, the flexible substrate has a three-layer structure wherein a laminated layer  60  is sandwiched between a pair of conductive layers  58 , the conductive layer  58  is formed of a copper foil, and the laminated layer  60  is formed of a polyimide film. In this manner, since each of the bridging portions  34   a  and  34   b  is formed of the soft flexible substrate, even if vibration occurs in the bridging portions  34   a  and  34   b  in any other direction except the longitudinal direction, the bridging portions  34   a  and  34   b  hardly fatigue, and so fracture of the bridging portions  34   a  and  34   b  is prevented. 
         [0037]      FIG. 8  shows a sixth embodiment of the present invention. 
         [0038]    According to this embodiment, in at least one of electrode members  40  and  40   b , e.g., the negative electrode member  40   a , a slit  62  as a hole portion is formed in the bridging portion  34   a  closest to a voltage supply side, i.e., a proximal end side in the plurality of bridging portions  34   a . Therefore, fatigue strength of this bridging portion  34   a  is smaller than fatigue strength of the bridging portion  34   a  on a voltage acceptance side, i.e., a distal end side with respect to the former bridging portion  34   a . In a case where the respective bridging portions  34   a  have the same fatigue strength, when the vibrator  20  vibrates ultrasonically, the bridging portion  34   a  on the voltage acceptance side may fracture before the other bridging portions  34   a . When the bridging portion  34   a  on the voltage acceptance side fractures, a change in electrostatic capacity of the vibrator  20  is small, matching of the system is maintained, and so the vibrator  20  may continue the vibration in an inappropriate vibration state. In this embodiment, since, in the plurality of bridging portions  34   a  and  34   b , fatigue strength of the bridging portions  34   a  and  34   b  closest to the voltage supply side is smaller than fatigue strength of the bridging portions  34   a  and  34   b  on the voltage acceptance side with respect to the former bridging portion  34   a , when the vibrator  20  vibrates ultrasonically, the former bridging portions  34   a  and  34   b  fracture first, the electrostatic capacity of the vibrator  20  is greatly changed, matching of the system is assuredly lost, and the system is securely stopped. Therefore, the vibrator  20  is prevented from continuing the vibration in the inappropriate vibration state. 
         [0039]    It is to be noted that the slit  62  may be formed in lead portions  36   a  and  36   b.    
         [0040]      FIG. 9  shows a seventh embodiment according to the present invention. 
         [0041]    In this embodiment, distal-end-side electrode plates  64   a  and  64   b  on the voltage acceptance side and proximal-end-side electrode members  66   a  and  66   b  on the voltage supply side are used as the electrode members  40   a  and  40   b . The electrode plates  68   a  and  68   b  at the most proximal ends of the distal-end-side electrode members  64   a  and  64   b  and the electrode plates  70   a  and  70   b  at the most distal ends of the proximal-end-side electrode members  66   a  and  66   b  are superimposed between the piezoelectric elements  30  adjacent to each other and are electrically connected with each other. Here, fatigue strength of a material forming the proximal-end-side electrode members  66   a  and  66   b  is smaller than fatigue strength of a material forming the distal-end-side electrode members  64   a  and  64   b . In this embodiment, the proximal-end-side electrode members  66   a  and  66   b  are formed of, e.g., phosphor bronze or nickel silver, and the distal-end-side electrode members  64   a  and  64   b  are formed of, e.g., beryllium copper or a titanium copper. When the vibrator  20  vibrates ultrasonically, like the sixth embodiment, the bridging portions  34   a  and  34   b  of the proximal-end-side electrode members  66   a  and  66   b  on the voltage supply side fracture first, and so the vibrator  20  is prevented from continuing the vibration in an inappropriate state. 
         [0042]      FIGS. 10 to 12  show a reference embodiment according to the present invention. 
         [0043]    In an electrical insulating member of the reference embodiment, insulating wrappings  68  are provided on the bridging portions  34   a  and  34   b  and the lead portions  36   a  and  36   b . In the vibration generating portion  28  of the vibrator  20 , the bridging portions  34   a  and  34   b  and the lead portions  36   a  and  36   b  are arranged near the electrode plates  32   a  and  32   b  having the opposite polar. Therefore, in a case where the insulating wrappings  68  are not provided on the bridging portions  34   a  and  34   b  and the lead portions  36   a  and  36   b , especially in a case where the vibrator  20  is small in size and the driving voltage is a high voltage in order to operate the vibrator  20  with a high output, short circuit may occur between the bridging portions  34   a  and  34   b  and the lead portions  36   a  and  36   b , and, the electrode plates  32   a  and  32   b  having opposite pole. In this embodiment, since the insulating wrappings  68  are provided on the bridging portions  34   a  and  34   b  and the lead portions  36   a  and  36   b , short circuit is prevented from occurring between the bridging portions  34   a  and  34   b  and the lead portions  36   a  and  36   b , and, the electrode plates  32   a  and  32   b  having opposite pole, and so the vibrator  20  can be reduced in the size and increased in the output. 
         [0044]    It is to be noted that insulating coating may be used in place of the insulating wrappings  68 . In a case where the insulating coating is used, coating is applied to the bridging portions  34   a  and  34   b  and the lead portions  36   a  and  36   b  by, e.g., a spray or a brush in a state where the electrode plates  32   a  and  32   b  of electrode members  40   a  and  40   b  are protected, before assembling. 
         [0045]    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.