JP2014011737A - Ultrasonic vibration device, ultrasonic vibration device manufacturing method, and ultrasonic medical equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ultrasonic vibration device that has heat resistance and prevents a short circuit between electrodes by preventing surface discharge between the electrodes in a construct made without lead.SOLUTION: An ultrasonic vibration device 2 comprises: a plurality of stacked piezoelectric single crystal plates 61; a plurality of electrodes 62, 63 having an area smaller than a front area and rear area of a piezoelectric single crystal plate 61 and placed between the plurality of piezoelectric single crystal plates 61; electric conduction parts 65, 66 for electrically connecting a positive electrode with other positive electrodes, and a negative electrode with other negative electrodes of the plurality of electrode plates 62, 63; on front and rear surfaces of the piezoelectric single crystal plate 61, flat region 61a where the electrode plates 62, 63 are not provided from an outer peripheral edge toward a center O by a prescribed length of L.

Description

  The present invention relates to an ultrasonic vibration device that excites ultrasonic vibration, a method of manufacturing the ultrasonic vibration device, and an ultrasonic medical apparatus including the ultrasonic vibration device.

  In recent years, ultrasonic medical devices include, for example, ultrasonic treatment tools that are used for hemostasis / incision in laparoscopic surgery and that use friction / fever caused by ultrasonic vibration. An ultrasonic transducer that generates sonic vibrations is provided.

  In laparoscopic surgery, since the operation is performed in the human body, the space used is small, so that the equipment used there is required to be small. On the other hand, in order to perform hemostasis / incision, high-power ultrasonic vibration is required. For this reason, there is a concern that the temperature rise of the ultrasonic vibrator that occurs when the small ultrasonic vibrator is driven with high power may cause damage such as burns on the human body. In addition, since the ultrasonic transducer is housed inside the probe tip, heat from the ultrasonic transducer is difficult to escape and the vibration characteristics during driving may be degraded.

  Therefore, there is a technology that changes the material of the ultrasonic transducer to PZT (lead zirconate titanate), which has been used in the past, to a piezoelectric single crystal with low heat generation during driving and good temperature characteristics of piezoelectric characteristics. is there. For example, Patent Document 1 discloses a laminated piezoelectric unit that uses a piezoelectric single crystal that has heat resistance and is non-lead as an alternative to PZT (lead zirconate titanate) as a vibrator material of a laminated piezoelectric ultrasonic wave generating element. A crystal ultrasonic wave generating element is disclosed. The multilayer piezoelectric single crystal ultrasonic wave generating element disclosed in Patent Document 1 uses a piezoelectric single crystal vibrator composed of a perovskite compound.

  Patent Document 1 discloses a technique of a laminated piezoelectric single crystal ultrasonic wave generating element that is polarized after bonding two or more single crystals composed of an ABO3 type perovskite structure using a metal material, heating and bonding them. Yes. Furthermore, in Patent Document 1, the electromechanical coupling coefficient is larger than the electromechanical coupling coefficient of the single crystal alone by bonding two or more single crystals composed of an ABO3 type perovskite structure through a metal material. A multilayered piezoelectric single crystal ultrasonic wave generating element having a value is also disclosed. And in patent document 1, the technique of using a laminated piezoelectric ultrasonic wave generation element for an ultrasonic probe is also disclosed.

  In the technique of this Patent Document 1, for example, a metal electrode is fired on a rectangular piezoelectric single crystal element, and then bonded by subjecting two or more piezoelectric single crystal elements with metal electrodes to each other and performing a heat treatment. An ultrasonic element is manufactured. By this method, the basic structure is not changed, and the bonding strength and electromechanical coupling coefficient can be improved as compared with the conventional PZT laminated piezoelectric ultrasonic wave generating element.

JP 2001-102650 A

  However, since the piezoelectric single crystal element has a higher impedance than PZT that has been used as a vibrator of a conventional multilayer piezoelectric ultrasonic wave generation element, a high voltage is required for high output driving, and creeping discharge between the electrodes is not generated. It may occur and short circuit.

  Therefore, the present invention has been made in view of the above circumstances, and is provided with heat resistance, and in a lead-free configuration, ultrasonic vibration that prevents a short-circuit between electrodes by preventing creeping discharge between the electrodes. An object of the present invention is to provide a device, a method for manufacturing the ultrasonic vibration device, and an ultrasonic medical apparatus including the ultrasonic vibration device.

  An ultrasonic vibration device according to an aspect of the present invention includes a plurality of stacked piezoelectric single crystal plates and an area between the plurality of piezoelectric single crystal plates having an area smaller than the front and back areas of the piezoelectric single crystal plates. A plurality of electrode plates, a current-carrying part that electrically connects the plurality of positive electrode plates or the negative electrodes, and a predetermined length from the front and back edges of the piezoelectric single crystal plate toward the center. A planar region in which the electrode plate is not provided.

  The ultrasonic vibration device manufacturing method according to one aspect of the present invention includes a plurality of piezoelectric single crystal plates stacked, and the plurality of piezoelectric single crystals having an area smaller than a front and back area of the piezoelectric single crystal plate. A plurality of electrode plates interposed between the plates, a current-carrying portion that electrically connects the plurality of electrode plate positive electrodes or the negative electrodes, and from the edge of the front and back surfaces of the piezoelectric single crystal plate toward the center An ultrasonic vibration device manufacturing method comprising: a planar region in which the electrode plate is not provided for a predetermined length, wherein the plurality of piezoelectric single crystal plates and the plurality of electrode plates are stacked. After the crystal plate block is formed, the outer peripheral portion of the piezoelectric single crystal plate block is collectively polished by a processing jig in accordance with the dimensions of the laminated vibrator.

  Furthermore, an ultrasonic medical device according to an aspect of the present invention includes a plurality of laminated piezoelectric single crystal plates, and an area smaller than the front and back areas of the piezoelectric single crystal plates, and between the plurality of piezoelectric single crystal plates. Predetermined from the outer peripheral edge side to the center on the front and back surfaces of the plurality of interposed electrode plates, the plurality of electrode plate positive electrodes or the negative electrodes, and the front and back surfaces of the piezoelectric single crystal plate. An ultrasonic vibration device comprising a plane region on which the electrode plate is not provided for the length of the probe, and a probe tip for treating the living tissue to which ultrasonic vibration generated by the ultrasonic vibration device is transmitted. To do.

  According to the present invention, an ultrasonic vibration device that has a heat resistance and has a lead-free configuration and prevents a short-circuit between electrodes by preventing creeping discharge between the electrodes, a method for manufacturing the ultrasonic vibration device, An ultrasonic medical apparatus provided with an acoustic vibration device can be provided.

Sectional drawing which shows the whole structure of the ultrasonic medical device of 1 aspect of this invention The figure which shows the schematic structure of the whole vibrator unit same as the above Sectional drawing which shows the whole structure of the ultrasonic medical device of the other aspect same as the above The perspective view showing the configuration of the ultrasonic transducer Side view showing the configuration of the ultrasonic transducer A perspective view showing the configuration of the laminated vibrator Side view showing the configuration of the laminated vibrator VIII-VIII sectional view of FIG. A plan view showing the structure of the piezoelectric single crystal plate and the electrode plate Sectional drawing which shows the structure of the laminated vibrator of the modification The perspective view which shows the structure of the laminated oscillator of a modification Sectional view showing the configuration of the piezoelectric single crystal plate and the electrode plate The graph showing the change in capacitance with respect to the ratio of the thickness of the piezoelectric single crystal plate and the length of the planar region where no electrode plate is provided. The perspective view which shows the structure of the laminated oscillator of a modification Sectional drawing which shows the structure of the laminated vibrator of the modification Sectional drawing which shows the structure of the laminated vibrator of the modification Sectional drawing which shows the structure of the laminated vibrator of the modification The perspective view which shows the structure of the laminated vibrator with the same insulation coating Cross-sectional view showing the structure of a laminated vibrator with insulation coating Sectional view showing the piezoelectric single crystal plate block A perspective view showing a processing jig for polishing the piezoelectric single crystal plate block Sectional view showing the processed laminated vibrator Sectional view showing a laminated vibrator with insulation coating

  Hereinafter, the present invention will be described with reference to the drawings. In the following description, the drawings based on each embodiment are schematic, and the relationship between the thickness and width of each part, the thickness ratio of each part, and the like are different from the actual ones. It should be noted that the drawings may include portions having different dimensional relationships and ratios between the drawings.

  1 is a cross-sectional view showing an overall configuration of an ultrasonic medical device, FIG. 2 is a diagram showing an overall schematic configuration of a transducer unit, and FIG. 3 is a cross-sectional view showing the overall configuration of an ultrasonic medical device according to another aspect. 4 is a perspective view showing the configuration of the ultrasonic transducer, FIG. 5 is a side view showing the configuration of the ultrasonic transducer, FIG. 6 is a perspective view showing the configuration of the laminated transducer, and FIG. 8 is a cross-sectional view taken along the line VIII-VIII of FIG. 7, FIG. 9 is a plan view showing the structure of the piezoelectric single crystal plate and the electrode plate, and FIG. 10 is a cross-sectional view showing the structure of the laminated vibrator of the modification. 11 is a perspective view showing the configuration of the laminated vibrator of the modified example, FIG. 12 is a cross-sectional view showing the configuration of the piezoelectric single crystal plate and the electrode plate, and FIG. 13 is a plane in which the thickness of the piezoelectric single crystal plate and the electrode plate are not provided. 14 is a graph showing the change in capacitance with respect to the ratio of the region length, and FIG. FIGS. 15 to 17 are cross-sectional views showing the configuration of a modified laminated vibrator, FIG. 18 is a perspective view showing the structure of a laminated vibrator with insulation coating, and FIG. 19 is the construction of a laminated vibrator with insulation coating. 20 is a cross-sectional view showing a piezoelectric single crystal plate block, FIG. 21 is a perspective view showing a processing jig for polishing the piezoelectric single crystal plate block, and FIG. 22 is a cross-section showing a processed laminated vibrator. FIG. 23 and FIG. 23 are cross-sectional views showing a laminated vibrator having an insulating coating.

(Ultrasonic medical device)
An ultrasonic medical device 1 shown in FIG. 1 includes a vibrator unit 3 having an ultrasonic vibrator 2 that mainly generates ultrasonic vibrations, and a handle unit 4 that treats the affected area using the ultrasonic vibrations. Is provided.

  The handle unit 4 includes an operation section 5, an insertion sheath section 8 including a long mantle tube 7, and a distal treatment section 30. The proximal end portion of the insertion sheath portion 8 is attached to the operation portion 5 so as to be rotatable about the axis. The distal treatment section 30 is provided at the distal end of the insertion sheath section 8. The operation unit 5 of the handle unit 4 includes an operation unit main body 9, a fixed handle 10, a movable handle 11, and a rotary knob 12. The operation unit body 9 is formed integrally with the fixed handle 10.

  A slit 13 through which the movable handle 11 is inserted is formed on the back side of the connecting portion between the operation unit main body 9 and the fixed handle 10. The upper part of the movable handle 11 extends into the operation unit main body 9 through the slit 13. A handle stopper 14 is fixed to the lower end of the slit 13. The movable handle 11 is rotatably attached to the operation unit main body 9 via a handle support shaft 15. The movable handle 11 is opened and closed with respect to the fixed handle 10 as the movable handle 11 rotates about the handle support shaft 15.

  A substantially U-shaped connecting arm 16 is provided at the upper end of the movable handle 11. The insertion sheath portion 8 includes a mantle tube 7 and an operation pipe 17 that is inserted into the mantle tube 7 so as to be movable in the axial direction. A large diameter portion 18 having a diameter larger than that of the distal end portion is formed at the proximal end portion of the outer tube 7. The rotary knob 12 is mounted around the large diameter portion 18.

  A ring-shaped slider 20 is provided on the outer peripheral surface of the operation pipe 19 so as to be movable along the axial direction. A fixing ring 22 is disposed behind the slider 20 via a coil spring (elastic member) 21.

  Further, the proximal end portion of the grip portion 23 is rotatably connected to the distal end portion of the operation pipe 19 via an action pin. This gripping part 23 constitutes a treatment part of the ultrasonic medical device 1 together with the distal end part 31 of the probe 6. When the operation pipe 19 moves in the axial direction, the grip portion 23 is pushed and pulled in the front-rear direction via the action pin. At this time, when the operation pipe 19 is moved to the hand side, the grip portion 23 is rotated clockwise about the fulcrum pin via the action pin. As a result, the gripping portion 23 rotates in the direction approaching the distal end portion 31 of the probe 6 (the closing direction). At this time, the living tissue can be grasped between the single-opening type grasping portion 23 and the distal end portion 31 of the probe 6.

  In this state where the living tissue is gripped, electric power is supplied from the ultrasonic power source to the ultrasonic vibrator 2 to vibrate the ultrasonic vibrator 2. This ultrasonic vibration is transmitted to the tip 31 of the probe 6. And the treatment of the biological tissue currently hold | gripped between the holding part 23 and the front-end | tip part 31 of the probe 6 is performed using this ultrasonic vibration.

(Vibrator unit)
Here, the vibrator unit 3 will be described.
As shown in FIG. 2, the transducer unit 3 is integrally assembled with an ultrasonic transducer 2 and a probe 6 that is a rod-shaped vibration transmission member that transmits ultrasonic vibration generated by the ultrasonic transducer 2. It is a thing.

  The ultrasonic transducer 2 is connected to a horn 32 that amplifies the amplitude of the ultrasonic transducer. The horn 32 is made of duralumin or a titanium alloy such as 64Ti (Ti-6Al-4V). The horn 32 is formed in a conical shape whose outer diameter becomes narrower toward the distal end side, and an outward flange 33 is formed on the base end outer peripheral portion. Here, the shape of the horn 32 is not limited to the conical shape, but may be an exponential shape in which the outer diameter decreases exponentially toward the tip side, or a step shape that gradually decreases toward the tip side. May be.

  The probe 6 has a probe main body 34 formed of a titanium alloy such as 64Ti (Ti-6Al-4V). On the proximal end side of the probe main body 34, the ultrasonic transducer 2 connected to the horn 32 is disposed. In this way, the transducer unit 3 in which the probe 6 and the ultrasonic transducer 2 are integrated is formed. The probe 6 has a probe main body 34 and a horn 32 screwed together, and the probe main body 34 and the horn 32 are joined.

  The ultrasonic vibration generated by the ultrasonic transducer 2 is amplified by the horn 32 and then transmitted to the distal end portion 31 side of the probe 6. The distal end portion 31 of the probe 6 is formed with a later-described treatment portion for treating living tissue.

  In addition, two rubber linings 35 are attached to the outer peripheral surface of the probe main body 34 at intervals of vibration node positions in the middle of the axial direction at intervals formed in a ring shape with an elastic member. These rubber linings 35 prevent contact between the outer peripheral surface of the probe main body 34 and an operation pipe 19 described later. That is, when assembling the insertion sheath portion 8, the probe 6 as a transducer-integrated probe is inserted into the operation pipe 19. At this time, the rubber lining 35 prevents contact between the outer peripheral surface of the probe main body 34 and the operation pipe 19.

  Further, the ultrasonic transducer 2 is electrically connected via an electric cable 36 to a power supply device main body (not shown) that supplies a current for generating ultrasonic vibration. The ultrasonic vibrator 2 is driven by supplying electric power from the power supply main body to the ultrasonic vibrator 2 through the wiring in the electric cable 36. The vibrator unit 3 includes an ultrasonic vibrator 2 that generates ultrasonic vibrations, a horn 32 that amplifies the generated ultrasonic vibrations, and a probe 6 that transmits the amplified ultrasonic vibrations.

  Note that the ultrasonic transducer 2 and the transducer unit 3 do not necessarily have to be accommodated in the operation unit main body 9 as shown in FIG. 1, for example, are accommodated in the operation pipe 19 as shown in FIG. May be. In the ultrasonic medical device 1 of FIG. 3, the electric cable 36 between the bending stop 52 of the ultrasonic transducer 2 and the connector 38 disposed at the base of the operation unit main body 9 is inserted into the metal pipe 37. Has been stored. Here, the connector 38 is not essential, and the electric cable 36 may be extended to the inside of the operation unit main body 9 and directly connected to the folding stop 52 of the ultrasonic transducer 2. The ultrasonic medical device 1 can improve the space saving in the operation unit main body 9 with the configuration as shown in FIG. The function of the ultrasonic medical device 1 in FIG. 3 is the same as that in FIG.

(Ultrasonic transducer)
Here, the ultrasonic transducer 2 as the ultrasonic vibration device of the present invention will be described below.
As shown in FIGS. 4 and 5, the ultrasonic transducer 2 of the transducer unit 3 includes a horn 32 that is screwed and connected to a probe main body 34 that is one of vibration transmission members in order from the tip, The laminated vibrator 41 is connected to the rear of the horn 32, and the cover body 51 covers the laminated vibrator 41 from the proximal end of the horn 32 to the electric cable 36. Note that the cover body 51 that covers the laminated vibrator 41 has a folding stop 52 that covers the wirings 36a and 36b of the electric cable 36 electrically connected to the two electrode pieces 47 and 48 at the base end portion.

  The laminated vibrator 41 is joined to a front mass 39 as a cylindrical metal block body in which disk-like insulating plates 42 and 43 are arranged in the front and rear sides and the front side is integrally formed with the horn 32 via the insulating plate 42. The rear side is joined to a back mass 44 as a cylindrical metal block body via an insulating plate 43. The front mass 39 and the back mass 44 are made of geralumin or a titanium alloy such as 64Ti (Ti-6Al-4V).

  As shown in FIGS. 6 to 8, the laminated vibrator 41 includes a plurality of, here, three piezoelectric single crystal plates formed of a heat-resistant non-lead single crystal material such as lithium niobate (LiNbO 3). 61 are stacked. Between these piezoelectric single crystal plates 61, for example, disk-shaped electrode plates (layers) 62, 63 in which a metal film such as gold is formed by vapor deposition or the like are interposed alternately. The electrode plates (layers) 62 and 63 are not limited to the configuration in which a metal film is deposited on the front and back surfaces of the piezoelectric single crystal plate 61, and may be a metal foil, a metal plate, or the like.

  These electrode plates 62 and 63 have an area smaller than the surface area of the piezoelectric single crystal plate 61 by a predetermined range. The electrode plates 62 and 63 are provided so that the centers thereof coincide with the centers of the piezoelectric single crystal plate 61. That is, the piezoelectric single crystal plate 61 has planar regions 61a on the front and back surfaces where the electrode plates 62 and 63 are not provided for a predetermined length (width) from the outer peripheral edge toward the center.

  More specifically, as shown in FIG. 9, the piezoelectric single crystal plate 61 has a radius r1 from the center O. The electrode plates 62 and 63 provided on the front and back surfaces of the piezoelectric single crystal plate 61 are within a radius r2 (r1> r2) from a common center O shorter than the radius r1 of the piezoelectric single crystal plate 61 by a predetermined length. Is provided. That is, the piezoelectric single crystal plate 61 is provided with the electrode plates 62 and 63 on the outer peripheral edge portions of the front and back surfaces by the length (r1-r2) between the radius r1 and the radius r2 of the electrode plates 62 and 63. It has a non-planar area 61a.

  As described above, the laminated vibrator 41 has the planar regions 61 a where the electrode plates 62 and 63 are not provided on both front and back surfaces of the outer peripheral portion of each piezoelectric single crystal plate 61, and the outer peripheral surface 61 b of each piezoelectric single crystal plate 61. By ensuring a predetermined creepage distance between the electrode plates 62 and 63, it is possible to prevent a short circuit due to creeping discharge between the electrode plates 62 and 63 during high output driving (high voltage).

In addition, the end portions of two electrode pieces 65 and 66, which are metal parts having a substantially U-shaped cross section as current-carrying portions, are electrically joined to the electrode plates 62 and 63 by solder, conductive adhesive, or the like. Yes. Here, these two electrode pieces 65 and 66 are disposed at substantially symmetrical positions so as not to short-circuit each other in the side circumferential portion of the laminated vibrator 41. The two electrode pieces 65 and 66 connect one electrode plate 62 and the other electrode plate 63 to each other in the front-rear direction of the laminated vibrator 41 so that the positive electrodes and the negative electrodes are electrically connected. ing.
Here, each electrode plate 62 and electrode piece 65 may be a metal part formed integrally. Similarly, each electrode plate 63 and the electrode piece 66 may also be metal parts formed integrally.

  That is, the positive electrode or the negative electrode is divided by the electrode plate 62 or the electrode plate 63, and the two electrode pieces 65 and 66 electrically connect the positive electrode portions or the negative electrode portions formed by the electrode plates 62 and 63 of the laminated vibrator 41. Connect. The two electrode pieces 47 and 48 are electrically connected to the wirings 36a and 36b of the electric cable 36 by welding and joining with solder or a conductive adhesive (see FIGS. 4 and 5).

  In the laminated vibrator 41, as shown in FIG. 10, an insulating material 67 is filled between the side peripheral surfaces of the piezoelectric single crystal plates 61 and the electrode plates 62 and 63 and the electrode pieces 65 and 66. By doing so, discharge from the electrode pieces 65 and 66 to the electrode plates 62 and 63 can also be prevented. Further, by providing the insulating material 67 in this way, the conductive adhesive that electrically connects the one electrode plate 62 and the other electrode plate 63 to each other is insulated instead of the electrode pieces 65 and 66. A wiring configuration formed on the surface of the material 67 may be used.

  Further, as shown in FIG. 11, the laminated vibrator 41 has two cables 68 covered with an outer skin of an insulator instead of the electrode pieces 65 and 66 in order to prevent discharge to the electrode plates 62 and 63. 69, the positive electrode portions or negative electrode portions of the electrode plates 62 and 63 may be electrically connected to each other. The cores of the cables 68 and 69 are electrically connected to the electrode plates 62 and 63 by soldering portions 68a and 69a such as solder and conductive adhesive.

  By the way, regarding the outer peripheral portion of the piezoelectric single crystal plate 61 including the planar region 61a where the electrode plates 62 and 63 are not provided on the outer peripheral edge portions of the front and back surfaces of the piezoelectric single crystal plate 61, as shown in FIG. The thickness (thickness) of the single crystal plate 61 is d, and the piezoelectric single crystal plate 61 in a direction orthogonal to the stacking direction from each end of the pair of electrode plates 62 and 63 sandwiching the piezoelectric single crystal plate 61 is used. The outer peripheral end portion including the planar region 61a of the piezoelectric single crystal plate 61 is accommodated in a square indicated by a broken line in the figure having the length d of each side, which is formed when the same distance as the thickness d is taken. It has become. That is, the length L of the planar region 61 a of the piezoelectric single crystal plate 61 is equal to or less than the plate thickness length d of the piezoelectric single crystal plate 61 (L ≦ d).

  As shown in the graph of FIG. 13, the piezoelectric single crystal plate 61 is provided with the electrode plates 62 and 63 until the ratio of the length L of the planar region 61a to the thickness d is 100%. Effective vibrations can also be excited in the outer peripheral portion which is not provided in the same manner as the portions where the electrode plates 62 and 63 are provided. That is, as shown in the graph of FIG. 13, when the ratio of the length L of the planar region 61a to the thickness d of the piezoelectric single crystal plate 61 exceeds 100%, the increase in capacitance is saturated.

  Therefore, in the piezoelectric single crystal plate 61, until the ratio of the length L of the planar region 61a to the thickness d reaches 100%, the entire outer peripheral portion where the electrode plates 62 and 63 are not provided functions as a dielectric. ing. However, in the piezoelectric single crystal plate 61, even if the length L of the planar region 61a is increased in order to increase the creepage distance, the portion beyond 100% of the thickness d does not work as a dielectric. become. In other words, the outer peripheral portion of the piezoelectric single crystal plate 61 that does not work as a dielectric is an unnecessary portion that does not work as a vibrator, and further impedes the performance as a vibrator (becomes a load). It is best to set the length to 100% or less with respect to the thickness d.

  Thereby, the laminated vibrator 41 accommodates the outer peripheral portion where the electrode plates 62 and 63 are not provided in the square portion formed with the thickness d of the piezoelectric single crystal plate 61 as one side. In the same way, effective vibrations can be excited in the same manner as the portions where the electrode plates 62 and 63 are provided, and generation of unnecessary vibrations due to the outer peripheral portion being a load can be prevented. In the piezoelectric single crystal plate 61, the creepage distance between the electrode plates 62 and 63 can be made longer by bringing the length L of the planar region 61a closer to the thickness d, so that it can be driven at high output (high voltage). Creeping discharge can be prevented.

  From the above description, the laminated vibrator 41 of the present embodiment has a heat resistance and a creepage distance between the electrode plates 62 and 63 to which a high voltage is applied using the lead-free piezoelectric single crystal plate 61. By ensuring the above, the creeping discharge between the electrode plates 62 and 63 is prevented to prevent a short circuit.

  Further, as shown in FIGS. 14 and 15, the piezoelectric single crystal plate 61 has an outer peripheral surface 61b in which the outer peripheral portion of the piezoelectric single crystal plate 61 has a circular arc shape (R shape) between the electrode plates 62 and 63. The creepage distance may be further increased. Furthermore, the cross-sectional shape of the outer peripheral portion of the piezoelectric single crystal plate 61 may be, for example, an outer peripheral surface 61b with chamfered corners as shown in FIG. 16, or an outer peripheral surface on which a plurality of irregularities are formed as shown in FIG. It may be 61b.

  Even in the configuration of the piezoelectric single crystal plate 61, as described above, the length L of the planar region 61a of the piezoelectric single crystal plate 61 is set to be equal to or less than the thickness d of the piezoelectric single crystal plate 61 (L ≦ d). The outer peripheral end portion of the piezoelectric single crystal plate 61 is accommodated in a square having a length d of each side.

  With these configurations, when the shape of the outer peripheral portion of the piezoelectric single crystal plate 61 is a circular arc shape or chamfered, the mechanical strength can be expected to be improved by eliminating the right-angled corner at the outer peripheral end portion of the piezoelectric single crystal plate 61. . Further, when a plurality of convex shapes are formed on the outer peripheral portion of the piezoelectric single crystal plate 61, it is possible to extend the creeping distance between the electrode plates 62 and 63 as much as possible.

  Further, as shown in FIGS. 18 and 19, the outer peripheral portion of the laminated vibrator 41 formed by laminating the piezoelectric single crystal plate 61 and the electrode plates 62 and 63 is covered with a highly insulating resin coating 71. Also good.

  The resin used for the coating is preferably a resin having a high insulating property and a low dielectric constant. For example, parylene (registered trademark: paraxylylene polymer) has a dielectric constant of about half that of epoxy resin, and can be coated by vapor deposition (in a room temperature environment) using a coating apparatus (withstand voltage). : About 5000V / 25um, heat resistance: about 450 ° C). Therefore, when the laminated vibrator 41 is manufactured, the piezoelectric single crystal plate 61 and the electrode plates 62 and 63 are laminated and the electrode pieces 65 and 66 are connected, and then parylene is deposited on the outer peripheral portion of the laminated vibrator 41 by vapor deposition. The coating process.

  According to this configuration, in the laminated vibrator 41, the insulating properties of the electrode plates 62 and 63 and the electrode pieces 65 and 66 are improved, and the resin coating 71 is buried in the unevenness of the outer peripheral portion of the piezoelectric single crystal plate 61 for protection. Therefore, there is an advantage that the mechanical strength is also increased.

  By the way, in the process of manufacturing the laminated vibrator 41, after the piezoelectric single crystal plate 61 and the electrode plates 62 and 63 are all laminated, the outer surface 61b of the piezoelectric single crystal plate 61 and the outer peripheral portion thereof are matched to a predetermined size. Unnecessary portions of the electrodes 62 and 63 may be collectively polished so that the planar region 61a is formed.

  Specifically, as shown in FIG. 20, a piezoelectric single crystal plate block 75 in which a piezoelectric single crystal plate 61 and electrode plates 62 and 63 are laminated is prepared. Then, as shown in FIG. 21, a processing jig 80 in which the stacked piezoelectric single crystal plate 61 and the electrode plates 62 and 63 in the piezoelectric single crystal plate block 75 are matched to the shape dimensions of the stacked vibrator 41 is rotated. The outer peripheral portion of the piezoelectric single crystal plate block 75 is subjected to batch polishing.

  At this time, the rotating shafts of the processing jig 80 and the piezoelectric single crystal plate block 75 are fixed, the processing blade 81 of the processing jig 80 is rotated around the shaft 82 at a high speed, and the piezoelectric single crystal plate block 75 is processed and processed. It is rotated at a lower speed than the tool 80. Then, as shown in FIG. 22, the laminated vibrator 41 in which the piezoelectric single crystal plate 61 and the electrode plates 62 and 63 are polished to a predetermined size is provided with electrode pieces 65 and 66 not shown here, As shown in FIG. 23, a resin coating 71 is applied.

  In this way, the piezoelectric single crystal plate block 75 is formed in advance, and the outer peripheral portion is collectively polished according to the dimensions of the laminated vibrator 41 by the processing jig 80, so that the number of processing steps can be reduced. Therefore, cost reduction can be achieved.

  The invention described in the above-described embodiment is not limited to the embodiment and modifications, and various modifications can be made without departing from the scope of the invention in the implementation stage. Further, the above embodiments include inventions at various stages, and various inventions can be extracted by appropriately combining a plurality of disclosed constituent elements.

  For example, even if some constituent requirements are deleted from all the constituent requirements shown in the embodiment, the described requirements can be deleted if the stated problem can be solved and the stated effect can be obtained. The configuration can be extracted as an invention.

DESCRIPTION OF SYMBOLS 1 ... Ultrasonic medical device 2 ... Ultrasonic vibrator 3 ... Vibrator unit 4 ... Handle unit 5 ... Operation part 6 ... Probe 7 ... Outer tube 8 ... Insertion sheath part 9 ... Operation part main body 10 ... Fixed handle 11 ... Movable handle DESCRIPTION OF SYMBOLS 12 ... Rotation knob 13 ... Slit 14 ... Handle stopper 15 ... Handle support shaft 16 ... Connection arm 17 ... Operation pipe 18 ... Large diameter part 19 ... Operation pipe 20 ... Slider 22 ... Fixing ring 23 ... Grip part 30 ... Tip treatment part 31 ... tip portion 32 ... horn 33 ... outward flange 34 ... probe body 35 ... rubber lining 36 ... electric cables 36a and 36b ... wiring 37 ... metal pipe 38 ... connector 39 ... front mass 41 ... laminated vibrators 42 and 43 ... insulating plate 44 ... back masses 47, 48 ... electrode pieces 51 ... cover body 52 ... breakage 61 ... piezoelectric single crystal plate 61a ... plane region 61b ... outer peripheral surface 6 , 63 ... electrode plate 65, 66 ... electrode pieces 67 ... insulating material 68, 69 ... cable 68a, 69a ... brazed portion 71 ... resin coating 75 ... piezoelectric single crystal plate block

Claims (8)

A plurality of laminated piezoelectric single crystal plates;
A plurality of electrode plates having an area smaller than the front and back area of the piezoelectric single crystal plate and interposed between the plurality of piezoelectric single crystal plates;
A current-carrying portion that electrically connects positive electrodes or negative electrodes of the plurality of electrode plates;
On the front and back surfaces of the piezoelectric single crystal plate, a planar region in which the electrode plate is not provided for a predetermined length from the outer peripheral edge toward the center;
An ultrasonic vibration device comprising:   The ultrasonic vibration device according to claim 1, wherein the predetermined length of the planar region is equal to or less than a thickness of the piezoelectric single crystal plate.   The ultrasonic vibration device according to claim 1, wherein the side surfaces of the plurality of piezoelectric single crystal plates have a circular arc shape in cross section.   The ultrasonic vibration device according to claim 1, wherein a corner portion of a side surface of the plurality of piezoelectric single crystal plates is chamfered.   The ultrasonic vibration device according to claim 1, wherein side surfaces of the plurality of piezoelectric single crystal plates have an uneven cross-sectional shape.   6. The superstructure according to claim 1, wherein a side periphery of a laminated vibrator in which the plurality of piezoelectric single crystal plates and the plurality of electrode plates are laminated is coated with an insulating resin. Sonic vibration device. The method for manufacturing the ultrasonic vibration device according to any one of claims 1 to 6,
After forming the piezoelectric single crystal plate block by laminating the plurality of piezoelectric single crystal plates and the plurality of electrode plates, the outer peripheral portion of the piezoelectric single crystal plate block is adjusted according to the dimensions of the laminated vibrator by a processing jig. A method for manufacturing an ultrasonic vibration device, characterized by performing batch polishing. The ultrasonic vibration device according to any one of claims 1 to 6,
A probe tip for treating a living tissue through transmission of ultrasonic vibration generated by the ultrasonic vibration device;
An ultrasonic medical device comprising:

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