JP5237010B2 - Ultrasonic vibrator and manufacturing method thereof - Google Patents

Description

  The present invention relates to an ultrasonic transducer that generates ultrasonic vibrations due to electrical distortion of a piezoelectric element, and a method for manufacturing the same.

  A Langevin type ultrasonic vibrator has been proposed in which a laminated unit of piezoelectric elements that are integrally fired is fitted into a recess provided in a metal vibration block (see, for example, Patent Document 1).

  In the ultrasonic vibrator of this document, a screw hole (female screw) is formed in the inner wall of a recess provided in the vibration block, and by fastening a bolt to the screw hole, the laminated unit of the piezoelectric elements is attached to the vibration block. It is fixed.

In addition, for example, a surgical handpiece that incorporates an ultrasonic transducer having a structure in which a laminated piezoelectric body housed in a recess in a housing is tightened by a horn formed with a male screw is known (for example, Patent Documents). 2).
Japanese Patent No. 3914050 JP 2004-160081 A

  However, such an ultrasonic transducer has a structure in which the piezoelectric element laminated unit is fixed by screwing as described above, so that the formation region of the screw structure is in the radial direction of the product (ultrasonic transducer main body). It is necessary to secure. In other words, fixing by screwing restricts the size of the piezoelectric element and the product body. For this reason, it is possible to reduce the size of the product and increase the output of the product by applying a large-diameter piezoelectric element. It becomes a hindering factor. In particular, for products for medical use, there is a strong demand for the development of small-sized and small-diameter ultrasonic transducers. For this reason, there is a demand for constructing an ultrasonic transducer without applying a screw structure as much as possible.

  Further, the holding force for holding (holding) the piezoelectric element inside the ultrasonic transducer as described above is one of the factors that affect the vibration performance of the ultrasonic transducer itself. However, as in Patent Documents 1 and 2 described above, the ultrasonic vibrator having a structure in which a screw is tightened on the piezoelectric element side is an obstacle to frictional force generated when the screw is tightened, and the piezoelectric element is The work of assembling with the holding (clamping) force is a relatively difficult work. In addition to this, the ultrasonic transducer having a structure in which a screw is tightened on the piezoelectric element side described above may cause displacement of the piezoelectric element from a predetermined design position due to the influence of torsional stress applied to the piezoelectric element. This is an element that causes variation in the vibration characteristics of the ultrasonic vibrator. In addition, there is a concern that, for example, an excessive mechanical stress is applied to the piezoelectric element due to the stress in the twisting direction.

  Therefore, the present invention has been made to solve the above-described problems, and can suppress the application of torsional stress to the piezoelectric element and can suppress variations in vibration characteristics, and can further reduce the size and increase the output. An object of the present invention is to provide an ultrasonic transducer capable of improving productivity and a manufacturing method thereof.

To achieve the above object, an ultrasonic transducer according to the present invention surrounds a piezoelectric element, a pair of sandwiching members that sandwich the piezoelectric element, and the pair of sandwiching members in cooperation with the piezoelectric element. Holders of Bei and a cover member that is caulked on at least one of the pair of clamping members in the state, the cover member, together are configured in a cylindrical shape, the pair of clamping members, said tubular cover member Each having an insertion portion inserted from one and the other opening portions of the cylindrical cover member so as to sandwich the piezoelectric element disposed inside, and each opening portion of the cylindrical cover member each of the peripheral portion of the said are caulked to each insertion portion of the pair of clamping members, characterized and this.

  In other words, according to the present invention, the piezoelectric element can be assembled as an internal component by caulking the cover member between a pair of clamping members that sandwich the piezoelectric element (without intentionally applying a screw structure or the like). It is possible to eliminate the necessity of securing the structure formation region in the product main body (ultrasonic vibrator main body). Therefore, according to the present invention, the degree of freedom in selecting the size of the piezoelectric element and the size of the product body is improved, thereby reducing the size of the ultrasonic vibrator and, on the other hand, the relatively large size. Higher output power of ultrasonic transducers can be realized by applying piezoelectric elements.

  Further, according to the present invention, since individual members can be joined together by caulking without applying a screw structure or the like as much as possible, by performing caulking while applying an appropriate load, for example, from both sides of a pair of sandwiching members, The piezoelectric element can be assembled with an appropriate holding (holding) force between the holding members without applying torsional stress or the like. Therefore, according to the present invention, it is possible to assemble the piezoelectric element with an appropriate holding force while suppressing misalignment at the time of assembling the piezoelectric element, it is possible to suppress variation in vibration characteristics of the ultrasonic vibrator, Furthermore, it is possible to prevent the piezoelectric element from being damaged due to mechanical stress.

  Further, in the case of joining by caulking in the present invention, unlike the case of applying welding or the like, for example, there is no need to heat and melt the joined portion to a high temperature, so freedom of material selection for the above-described sandwiching member and cover member It is possible to increase the degree, and it is not necessary to install relatively expensive equipment for welding, so that the productivity of the ultrasonic transducer can be improved.

In the ultrasonic transducer manufacturing method of the present invention, the cover member is disposed at a position surrounding the piezoelectric element in cooperation with the pair of sandwiching members while arranging the pair of sandwiching members at positions sandwiching the piezoelectric element from both sides. a member placing step of placing a said cover member crimping crimping step to the pair of clamping member in a state where the piezoelectric element through the pair of clamping members disposed in said member disposing step is pressurized, And the cover member is configured in a cylindrical shape, and the pair of clamping members sandwich the piezoelectric element disposed inside the cylindrical cover member. Insertion portions that can be respectively inserted from one opening portion and the other opening portion, and in the caulking step, the insertion portions of the pair of sandwiching members respectively inserted into the cylindrical cover members. Each of the peripheral edge of each opening portion of the cylindrical cover member and said caulking.

  According to the present invention, it is possible to suppress the application of torsional stress to the piezoelectric element and to suppress variations in vibration characteristics, and to improve productivity in addition to miniaturization and higher output. It is possible to provide an ultrasonic transducer and a method for manufacturing the same.

The best mode for carrying out the present invention will be described below with reference to the drawings.
[First Embodiment]
FIG. 1 is a front view showing the ultrasonic transducer 1 according to the first embodiment of the present invention in a partial cross section. FIG. 2 is an exploded view of some components of the ultrasonic transducer 1. FIG. FIG. 3 is a diagram for explaining a method of manufacturing the ultrasonic transducer 1.

  The ultrasonic transducer 1 according to the present embodiment is used as a vibration source for a handheld ultrasonic device such as an ultrasonic cutter or an ultrasonic calculus remover. That is, as shown in FIGS. 1 and 2, the ultrasonic transducer 1 is formed in a substantially cylindrical shape having a total length of 21.9 mm and a maximum outer diameter of 4.0 mm, for example, and includes a plurality of piezoelectric elements 8. 9, 10, 11, a front plate 2 and a backing plate 3 as a pair of sandwiching members that sandwich the piezoelectric elements 8, 9, 10, 11, and a side plate 12 as a cover member. It is configured.

  The piezoelectric elements 8, 9, 10, and 11 are integrally fired together with electrodes (silver electrodes) 14, 15, 16, 17, 18, conductor patterns 23, 25, and an insulating layer 24 made of silver palladium, etc. The unit 28 is configured.

  The piezoelectric elements 8, 9, 10, and 11 are made of a piezoelectric ceramic material such as PZT (lead zirconate titanate) or barium titanate, and have a rectangular flat plate shape of 2.5 mm square, or a diameter of 2.5 mm, for example. It is formed in a disk shape of size. The piezoelectric elements 8, 9, 10, and 11 are polarized in the thickness direction, and have a positive electrode or a negative electrode on the front surface or the back surface.

  That is, the piezoelectric element unit 28 includes the piezoelectric elements 8, 9, 10, 11 and the electrodes 14, 15, 16, 17, so that the piezoelectric elements 8, 9, 10, 11 are electrically connected in parallel. 18 and the conductor patterns 23 and 25 and the insulating layer 24 are laminated and fired integrally. Here, the insulating layer 24 is made of an electrically insulating resin material, ceramic, or the like, prevents a short circuit between the positive electrode conductor pattern 25 and the front plate 2, and the piezoelectric elements 8, 9, 10, In order to avoid the 11 side locally pressing the front plate 2 side (to effectively transmit the ultrasonic vibration generated on the piezoelectric elements 8, 9, 10, 11 side to the front plate 2 side) Is provided.

  As shown in FIGS. 1 and 2, the ultrasonic transducer 1 is provided with a positive lead wire 19 and a negative lead wire 20 each formed of a covered wire. The positive lead wire 19 is led out of the backing plate 3 from the side of the piezoelectric elements 8, 9, 10, 11 while being inserted through a through hole 3 c formed in the backing plate 3. On the other hand, the negative lead wire 20 is fixed in a state of being in pressure contact with the surface (outer surface) of the backing plate 3 through a lead fixing tool 21 in order to take a body ground.

  More specifically, the electrodes 15 and 17 serving as positive electrodes are connected to the positive lead wire 19 through the conductor pattern 25. On the other hand, the electrodes 14, 16 and 18 as negative electrodes are connected to the negative lead wire 20 through the conductor pattern 23 and the body of the backing plate 3. Further, the peripheral surface (side wall surface) of the piezoelectric element unit 28 electrically connected to the lead wires 19 and 20 is covered with an insulating layer 22. The insulating layer 22 is made of an insulating tape such as a polyimide film or a resin ring, and ensures the electrical insulation of the piezoelectric element unit 28 with respect to the inner wall surface of the side plate 12. Further, such an insulating layer 22 may be formed by applying a liquid insulating material such as an insulating paste to the peripheral surface of the piezoelectric element unit 28. Alternatively, the insulating layer may be formed by coating the inner wall surface of the cylindrical side plate 12 with an insulating coat or the like.

Next, the structure of the front plate 2, the backing plate 3, and the side plate 12 and the joining structure of these members will be described.
As shown in FIGS. 1 and 2, the front plate 2 is configured as a substantially frustoconical metal block provided with a step having a small diameter on the base end side (piezoelectric element side) using a titanium alloy or the like as a material. ing. The front plate 2 has a length in the axial direction of, for example, 1 / 4λ with respect to the resonance frequency λ of the ultrasonic transducer 1 body, and ultrasonic vibration generated on the piezoelectric element unit 28 side. And the most advanced surface is the vibration radiating surface 7. On the other hand, the backing plate 3 is similarly configured as a substantially cylindrical metal block using a titanium alloy or the like as a constituent material and provided with a step having a small diameter on the tip side (piezoelectric element side). The lead wires 19 and 20 described above are drawn out from the most proximal end surface of the backing plate 3.

  As shown in FIGS. 1 and 2, the side plate 12 is formed in a cylindrical shape (cylindrical shape) using the titanium alloy or the like as a material. The side plate 12 is caulked to each of the front plate 2 and the back plate 3 in a state of surrounding the piezoelectric elements 8, 9, 10, 11 in cooperation with the front plate 2 and the back plate 3. More specifically, the side plate 12 surrounds the piezoelectric elements 8, 9, 10, 11 while being interposed between the front plate 2 and the backing plate 3, and each of the front plate 2 and the backing plate 3. And caulking rings 5 and 6. The caulking rings 5 and 6 that are annular locking members are made of, for example, duralumin.

  Further, the front plate 2 and the backing plate 3 are arranged on one side of the cylindrical side plate 12 so as to sandwich the piezoelectric elements 8, 9, 10, 11 (piezoelectric element unit 28) disposed inside the cylindrical side plate 12. And insertion portions 2a and 3a respectively inserted from the other opening portions 12a and 12b. The outer diameter portions of the insertion portions 2a and 3a and the inner diameter portion of the cylindrical side plate 12 are formed with dimensions that fit each other. Further, the insertion portion 2a of the front plate 2 is provided with a counterbore portion 2c in which the most proximal end surface is slightly depressed. The piezoelectric element unit 28 is sandwiched between the bottom surface of the spot facing portion 2c provided in the insertion portion 2a on the front plate 2 side and the foremost surface of the insertion portion 3a on the backing plate 3 side.

  Moreover, each peripheral part of the opening parts 12a and 12b opened to both ends of the side plate 12 is constituted by thin-walled parts 12c and 12d that are fitted (inserted) into the caulking rings 5 and 6, respectively. That is, as shown in FIGS. 1 and 2, the thin portions 12 c and 12 d (outer diameter portions) of the side plate 12 are inserted into the caulking rings 5 and 6, respectively, and the openings 12 a and 12 b of the side plate 12 are inserted. In a state where the insertion portions 2a and 3a are inserted and the piezoelectric element unit 28 is sandwiched, the thin portions 12c and 12d of the side plate 12 are the root portions 2b and 3b of the insertion portions 2a and 3a in the front plate 2 and the backing plate 3, respectively. It is caulked by caulking rings 5, 6 (small diameter portions of respective step portions of the front plate 2 and the backing plate 3).

  Here, in the state where the side plate 12 is interposed between the front plate 2 and the backing plate 3 sandwiching the piezoelectric element unit 28, each step surface on the base side of the insertion portions 2a and 3a of the front plate 2 and the backing plate 3 ( The axial length of the side plate 12 is such that a slight clearance is generated between the vibration radiating surface 7 or each step surface parallel to the most proximal end surface of the backing plate 3 and both ends of the cylindrical side plate 12. Is set. That is, as shown in FIG. 3, in a state where the piezoelectric elements 8, 9, 10, 11 (piezoelectric element unit 28) are pressed through the front plate 2 and the backing plate 3, the side plate 12 has the front plate 2 and the backing plate. It is squeezed to each of three. Thereby, the improvement of the vibration transmission property from the piezoelectric elements 8, 9, 10, 11 side to the front plate 2 side is achieved.

Next, a method for manufacturing the ultrasonic transducer 1 configured as described above will be described mainly with reference to FIGS.
As shown in FIG. 2, first, the piezoelectric elements 8, 9, 10, 11, electrodes 14, 15, 16, 17, 18, so that the piezoelectric elements 8, 9, 10, 11 are electrically in parallel. A baking process is performed in a state where the conductor patterns 23 and 25 and the insulating layer 24 are laminated and the piezoelectric element unit 28 is integrally fired. Subsequently, the peripheral surface (side wall surface) of the piezoelectric element unit 28 is covered with the insulating layer 22, and then, for example, lead wires 19 and 20 are wired.

  Next, as shown in FIGS. 2 and 3, the front plate 2 and the backing plate 3 are disposed while the front plate 2 and the backing plate 3 are arranged at positions where the piezoelectric element unit 28 (piezoelectric elements 8, 9, 10, 11) is sandwiched from both sides. The side plate 12 is arranged at a position surrounding the piezoelectric element unit 28 in cooperation with the plate 3. More specifically, the side plate 12 with the caulking rings 5 and 6 attached to the thin wall portions 12c and 12d is disposed at a position surrounding the piezoelectric element unit 28 (piezoelectric elements 8, 9, 10, and 11). The front plate 2 and the backing plate 3 are disposed at positions where the side plate 12 and the piezoelectric element unit 28 are sandwiched from both sides (inserted portions 2a and 3a are inserted into the opening portions 12a and 12b of the side plate 12). Furthermore, as shown in FIG. 3, the piezoelectric element unit 28 is pressed with an appropriate load from the P1 and P2 directions through the front plate 2 and the backing plate 3 arranged in this manner, and the caulking rings 5 and 6 are connected. Caulking is performed by pressing the periphery inward. At this time, the thin portions 12c and 12d at both ends of the side plate 12 together with the caulking rings 5 and 6 are plastically deformed in the direction of reducing the diameter, whereby the front plate 2 and the backing plate 3 (the root portions 2b of the insertion portions 2a and 3a). 3b) and the side plate 12 (thin wall portions 12c, 12d) are integrally coupled. After the above-described caulking process, the ultrasonic vibrator 1 shown in FIG. 1 can be obtained.

  As described above, according to the ultrasonic transducer 1 and the manufacturing method thereof of the present embodiment, between the front plate 2 and the backing plate 3 that sandwich the piezoelectric elements 8, 9, 10, 11 (piezoelectric element unit 28). By caulking the side plate 12, the piezoelectric elements 8, 9, 10, and 11 can be assembled as internal parts without applying a screw structure or the like. It is not necessary to secure it in one main body. Therefore, the degree of freedom in selecting the size of the piezoelectric element and the size of the product body is improved, which makes it possible to reduce the size of the ultrasonic vibrator and, on the other hand, to apply a relatively large size piezoelectric element. Realization of high-power acoustic transducers. Furthermore, in the present embodiment, as described above, since a screw structure or the like is unnecessary, it is possible to reduce the component cost.

  Further, according to the ultrasonic vibrator 1 and the manufacturing method thereof of the present embodiment, the individual members are joined together by caulking without applying the screw structure as described above. For example, by performing caulking while applying an appropriate load from both sides, the piezoelectric element is applied to the front plate 2 and the backing plate without applying torsional stress or the like to the piezoelectric elements 8, 9, 10, 11 (piezoelectric element unit 28). It is possible to incorporate between the three with an appropriate holding (holding) force. As a result, it is possible to assemble the piezoelectric element with an appropriate holding force while suppressing misalignment during the assembly of the piezoelectric element, thereby suppressing variations in vibration characteristics of the ultrasonic vibrator, and further, mechanical It is also possible to prevent the piezoelectric element from being damaged due to stress. Moreover, in this embodiment, unlike the case where welding etc. are applied to the joining of members, for example, it is not necessary to heat and melt the parts to be joined to high temperatures, so the front plate 2, backing plate 3 and side plate 12 The degree of freedom in selecting materials can be increased (materials with a high melting point can be easily selected), and there is no need to install relatively expensive equipment for welding. Can be improved.

[Second Embodiment]
Next, a second embodiment of the present invention will be described with reference to FIG. Here, FIG. 4 is a front view showing the ultrasonic transducer 31 according to this embodiment in a partial cross section. In FIG. 4, the same components as those provided in the ultrasonic transducer 1 of the first embodiment shown in FIGS. 1 to 3 are assigned the same reference numerals and explanations thereof are omitted. .

  As shown in FIG. 4, the ultrasonic transducer 31 of this embodiment is replaced with a front plate 2, a backing plate 3 and a side plate 12 provided in the ultrasonic transducer 1 of the first embodiment. A face plate 32, a backing plate 33 and a side plate 34 are provided, and the front plate 32 and the backing plate 33 and the side plate 34 are caulked without using a caulking ring. That is, the front plate 32, the backing plate 33, and the side plate 34 are made of duralumin or soft iron, which is a relatively soft metal material, so as to be easily plastically deformed during caulking.

  Further, in order to make it easier for the meat on the side plate 34 side to bite into the front plate 32 and the backing plate 33 side during caulking, as shown in FIG. 4, the insertion portions 2a and 3a of the front plate 32 and the backing plate 33 are inserted. Concavities and convexities are formed on the surfaces (caulking portions) of the root portions 32b and 33b. The unevenness formed in the caulking portion may be provided on the side plate 34 side (inner wall surfaces of the thin portions 12c and 12d), or the front plate 32, the backing plate 33, and the side plate 34. And may be provided on both sides.

  That is, the ultrasonic transducer 31 of this embodiment has the thin portions 12c and 12d at both ends of the side plate 34 in a state where the piezoelectric element unit 28 is pressurized with an appropriate load through the front plate 32 and the backing plate 33. By performing caulking processing by pressing the periphery inward, the meat on the inner wall side of the thin wall portions 12c and 12d bites into the irregularities on the surface of the root portions 32b and 33b in the insertion portions 32a and 33a of the front plate 32 and the backing plate 33. Thereby, the front plate 32 and the backing plate 33 and the side plate 34 are integrally joined.

  Therefore, according to the ultrasonic transducer 31 and the manufacturing method thereof according to the present embodiment, it is possible to suppress the application of torsional stress to the piezoelectric elements 8, 9, 10, and 11 and to suppress variations in vibration characteristics, Moreover, miniaturization and high power can be realized while improving productivity. In particular, in this embodiment, the caulking ring applied in the first embodiment is not necessary, so that the manufacturing cost can be reduced.

[Third Embodiment]
Next, a third embodiment of the present invention will be described with reference to FIG. Here, FIG. 5 is a front view showing the ultrasonic transducer 41 according to this embodiment in a partial cross section. In FIG. 5, the same components as those provided in the ultrasonic transducer 1 of the first embodiment shown in FIGS. 1 to 3 are denoted by the same reference numerals and description thereof is omitted. .

  As shown in FIG. 5, the ultrasonic transducer 41 of this embodiment deletes the caulking ring 5 provided in the ultrasonic transducer 1 of the first embodiment and replaces the front plate 2 and the side plate 12 with each other. And a front plate 42 having a cover portion 42a. That is, the front plate 42 is realized by configuring the front plate 2 and the side plate 12 of the first embodiment with a single member.

  The ultrasonic transducer 41 is caulked by pressing the periphery of the caulking ring 6 inward while pressing the piezoelectric element unit 28 with an appropriate load through the front plate 42 and the backing plate 3. The thin portion 12d of the cover portion 42a of the front plate 42 together with the ring 6 is plastically deformed in the radial direction, whereby the cover portion 42a of the front plate 42 (part of the side plate 12 of the first embodiment) and the backing plate 3 are formed. (The base portion 3b of the insertion portion 3a) are joined to each other.

  5 illustrates a form in which the front plate 42 and the backing plate 3 are caulked through the caulking ring 6, but instead of this, the front plate 42 and the relatively soft metal material such as duralumin are used. While forming the backing plate 3, by forming irregularities on the inner wall of the thin wall portion 12d provided on the cover portion 42a of the front plate 42 and the surface of the root portion 3b provided on the insertion portion 3a of the backing plate 3, etc. The caulking ring 6 may be deleted and the front plate 42 and the backing plate 3 may be caulked.

  Therefore, according to the ultrasonic transducer 41 of the present embodiment, in addition to the effects of the first or second embodiment, the number of parts to be caulked and the number of parts are reduced, thereby reducing the part cost and improving the production efficiency. Can be achieved.

[Fourth Embodiment]
Next, a fourth embodiment of the present invention will be described with reference to FIG. Here, FIG. 6 is a front view showing a partial cross section of the ultrasonic transducer 51 according to this embodiment. In FIG. 6, the same components as those provided in the ultrasonic transducer 1 of the first embodiment shown in FIGS. .

  As shown in FIG. 6, the ultrasonic transducer 51 of this embodiment has a cover portion 53a in place of the backing plate 3 and the side plate 12 provided in the ultrasonic transducer 1 of the first embodiment. A backing plate 53 is provided. That is, the backing plate 53 is realized by configuring the backing plate 3 and the side plate 12 of the first embodiment with a single member.

  The ultrasonic vibrator 51 is caulked by pressing the periphery of the caulking ring 5 inward in a state where the piezoelectric element unit 28 is pressurized with an appropriate load through the front plate 2 and the backing plate 53. The thin portion 12c of the cover portion 53a of the backing plate 53 together with the ring 5 is plastically deformed in the radial direction, whereby the cover portion 53a of the backing plate 53 (the constituent part of the side plate 12 of the first embodiment) and the front plate 2 (The root portion 2b of the insertion portion 2a) are joined to each other.

  6 illustrates a form in which the front plate 2 and the backing plate 53 are caulked through the caulking ring 5, but instead of this, the front plate 2 and the relatively soft metal material such as duralumin are used. While forming the backing plate 53, by forming irregularities on the inner wall of the thin portion 12c provided on the cover portion 53a of the backing plate 53 and the surface of the root portion 2b provided on the insertion portion 2a of the front plate 2, etc. The caulking ring 5 may be deleted, and the front plate 2 and the backing plate 53 may be caulked.

  Therefore, according to the ultrasonic transducer 51 of the present embodiment, as with the effect of the third embodiment, the caulking location and the number of components are reduced, so that it is possible to reduce component costs and improve production efficiency. it can.

[Fifth Embodiment]
Next, a fifth embodiment of the present invention will be described with reference to FIG. Here, FIG. 7 is a front view showing a partial cross section of the ultrasonic transducer 71 according to this embodiment. In FIG. 7, the same components as those provided in the ultrasonic transducer 1 of the first embodiment shown in FIGS. .

  In addition to the configuration of the ultrasonic transducer 1 of the first embodiment, the ultrasonic transducer 71 of this embodiment further includes buffer members 72 and 73 that function as a damper material that attenuates unnecessary vibration, and a heat shrinkable tube 74. It is prepared for. The buffer member 72 is formed in a ring shape, for example, and is fixed to a position straddling the respective peripheral surfaces of the front plate 2 and the side plate 12 via an adhesive or the like. On the other hand, the buffer member 73 is formed in a columnar shape, for example, and is fixed to the most proximal end surface of the backing plate 3 via the heat shrinkable tube 74.

  These buffer members 72 and 73 are provided to remove unnecessary vibrations (mainly vibrations other than the vibration bands generated by the piezoelectric elements 8, 9, 10, and 11) that can occur in the main body of the ultrasonic vibrator 71. . That is, the buffer members 72 and 73 are made of a material having at least a lower hardness than the front plate 2 and the backing plate 3 made of titanium alloy. Specifically, as a constituent material of the buffer members 72 and 73, for example, a urethane resin containing lead titanate is applied. Further, such buffer members 72 and 73 protruding from the outer shape of the ultrasonic vibrator main body have a function of removing unnecessary vibrations, as well as a housing of an ultrasonic device such as an ultrasonic cutter or an ultrasonic calculus remover. It is also used as an attached portion (a convex portion to be fitted with a concave portion provided in a casing of an ultrasonic device) when the ultrasonic vibrator 71 is attached to the inside as a vibration source (internal part).

  Here, the buffer member 73 has, for example, a silicone resin-based or fluororesin-based heat-shrinkable tube 74 attached to the base end portion of the backing plate 3, and powdery lead titanate in the heat-shrinkable tube 74. After filling with the molten urethane resin, it is fixed to the most proximal end surface of the backing plate 3 by performing a heat treatment.

  In addition, in FIG. 7, although the buffer member 72,73 (and heat contraction tube 74) has illustrated the aspect attached with respect to the ultrasonic transducer | vibrator 1 shown in FIGS. 1-3, it replaces with this. Buffer members 72, 73 may be attached to the ultrasonic transducers 31, 41, 51 shown in FIGS. Further, the ultrasonic transducer main body may be configured by removing the heat shrinkable tube 74 from the backing plate 3 after the buffer member 73 is fixed.

  As described above, according to the ultrasonic transducer 71 according to the present embodiment, in addition to the effects of any of the above-described embodiments, unnecessary vibration that may occur in the ultrasonic transducer main body can be removed, and A portion to be attached to the housing of the ultrasonic device can be configured, and furthermore, vibration that can be transmitted to the housing of the ultrasonic device (for example, a handy type ultrasonic device main body) can be attenuated.

[Sixth Embodiment]
Next, a sixth embodiment of the present invention will be described with reference to FIGS. Here, FIG. 8 is an exploded perspective view of the ultrasonic transducer 81 according to this embodiment, and FIG. 9 is a front view showing the ultrasonic transducer 81 in a partial cross section. FIG. 10 is a front view of the ultrasonic transducer 81 disassembled and a part thereof is shown in cross section. FIG. 11 is a detailed view of a portion A of the side plate 92 shown in FIG. Further, FIG. 12 is a cross-sectional view showing the piezoelectric element unit 100 built in the ultrasonic transducer 81.

  The ultrasonic transducer 81 of this embodiment is a Langevin type ultrasonic transducer used as a vibration source of a grasping type (handling type) ultrasonic application device such as an ultrasonic scalpel or an ultrasonic calculus remover. That is, as shown in FIGS. 9 to 11, the ultrasonic transducer 81 includes a piezoelectric element unit 100 including piezoelectric elements 88, 89, 90, and 91, a front plate 82 and a backing plate 83 as a pair of clamping members. And a side plate 92 as a cover member.

  The front plate 82 and the backing plate 83 are constituted by cylindrical metal blocks made of titanium (Ti), a titanium alloy, stainless steel, or the like. The side plate 92 is formed in a cylindrical shape (cylindrical shape) using a material such as titanium, a titanium alloy, or stainless steel. Further, as shown in FIG. 10, the piezoelectric elements 88 to 91 (piezoelectric element unit 100) are sandwiched between a front plate 82 that is one clamping member and a backing plate 83 that is the other clamping member.

  As shown in FIG. 10, the side plate 92 cooperates with the front plate 82 and the backing plate 83 to surround the piezoelectric element unit 100 having the piezoelectric elements 88 to 91. It is caulked to at least one of them (in this embodiment, it is caulked to the backing plate 83).

  Here, the structure of the piezoelectric element unit 100 will be described. As shown in FIG. 12 (and FIG. 9, FIG. 10), the piezoelectric element unit 100 includes a plurality of disk-shaped piezoelectric elements 88 to 91 and a positive electrode terminal that is a disk-shaped electrode plate for positive and negative electrodes. Plates 95 and 97 and negative electrode terminal plates 94, 96 and 98, insulating layers 101 and 102, and conductive layers 103 and 104 are provided. The piezoelectric element unit 100 is integrated in a form in which a plurality of electrode plates composed of the positive electrode terminal plates 95 and 97 and the negative electrode terminal plates 94, 96, and 98 and a plurality of piezoelectric elements 88 to 91 are alternately stacked. ing.

  The positive terminal plates 95 and 97 and the negative terminal plates 94, 96, and 98 are made of beryllium copper or the like with a diameter of 4 mm and a thickness of 0.1 mm, for example. On the other hand, the piezoelectric elements 88 to 91 are formed, for example, with a diameter of 4 mm and a thickness of 1 mm, and an electrode layer serving as a positive electrode or a negative electrode is formed on each circular main surface (both end surfaces). That is, the manufacturing method of the piezoelectric elements 88 to 91 applies lead zirconate titanate (PZT) as a constituent material, and after press molding and firing, applies a conductive paste to each main surface, and further performs a polarization treatment in oil. Is polarized in the thickness direction. Thereafter, grinding and polishing are performed so as to obtain a desired shape, and silver (Ag) vapor deposition is performed on each main surface to form piezoelectric elements 88 to 91 having electrode layers.

  Here, the piezoelectric element units 100 are alternately stacked so that the positional relationship between the positive and negative electrodes of adjacent piezoelectric elements is reversed. Further, as will be described later, as shown in FIG. 12, the electrodes of the individual piezoelectric elements are drawn out by connecting the positive electrodes and the negative electrodes, whereby the plurality of piezoelectric elements 88 to 91 in the piezoelectric element unit 100 are connected to each other. Electrically connected in parallel.

  The piezoelectric elements 88 to 91 are not limited to those obtained by the above manufacturing method. For example, a piezoelectric element having a desired shape can be cut out from a raw material of a plate-like piezoelectric element polarized in the thickness direction by cutting processing such as ultrasonic processing. It is also possible to obtain a piezoelectric element by applying a conductive paste to each main surface (each end surface) of an unfired molded body and further laminating and integrating it, followed by firing and polarization treatment.

  As shown in FIG. 12, the insulating layer 101 is formed so as to cover a part of a side surface 96c of the negative electrode terminal plate 96 (the outer peripheral surface of the negative electrode terminal plate 96 exposed as an outer diameter portion of the piezoelectric element unit 100). . Further, the insulating layer 102 is formed so as to cover a part of the side surface 95 c of the positive electrode terminal plate 95. Such insulating layers 101 and 102 are configured by, for example, attaching an insulating film having electrical insulation or applying and solidifying an insulating paste.

  On the other hand, as shown in FIG. 12, the conductive layer 103 is formed between the main surfaces 96a and 96b of the negative electrode terminal plate 96 and the positive electrode terminal plates 95 and 97 (side surfaces) adjacent to each other through the piezoelectric elements 89 and 90, respectively. Are connected from the outside of the insulating layer 101 so as not to be short-circuited with the negative electrode (connected through the insulating layer). On the other hand, the conductive layer 104 is not short-circuited with the positive electrode between the main surfaces 95a and 95b of the positive electrode terminal plate 95 and the negative electrode terminal plates 94 and 96 (side surfaces thereof) adjacent to each other through the piezoelectric elements 88 and 89, respectively. Connection is made from the outside of the insulating layer 102. These conductive layers 103 and 104 are configured, for example, by attaching a conductive film or applying and solidifying a conductive paste. Note that the negative electrode terminal plate 96 and the negative electrode of the piezoelectric element 88 main body are formed by the conductive layer 104 from the outside of the insulating layer 102 on the premise that the body ground of the ultrasonic vibrator 81 main body (front plate 82 and backing plate 83) is used. By connecting (electrode layer), the negative electrode terminal plate 94 and the negative electrode terminal plate 98 at both ends of the piezoelectric element unit 100 may be deleted. In this case, the part cost can be reduced.

  In the piezoelectric element unit 100, as shown in FIG. 12 (FIGS. 9 and 10), a lead wire 105 is connected to a conductive layer 103 that connects the positive electrode terminal plate 95 and the positive electrode terminal plate 97 to each other. The lead wire 105 is constituted by a covered wire in which a core wire 105a is covered with a covering layer 105b. One end portion of the core wire 105a of the lead wire 105 is connected to the conductive layer 103 via a connection portion 105c obtained by solidifying solder or the like. As shown in FIGS. 9 and 10, the lead wire 105 is inserted into a lead wire lead-out hole 83c formed in an insertion portion 83a (described later) of the backing plate 83, and further, through the notch portion 83d ( It is drawn out of the ultrasonic transducer 81 (from the inside of the front plate 82, the backing plate 83, and the side plate 92).

  Further, as shown in FIGS. 9 and 10, the piezoelectric element unit 100 main body including the insulating layers 101 and 102, the conductive layers 103 and 104, one end portion of the lead wire 105 and the connection portion 105 c thereof, and the piezoelectric element unit 100 main body A short-circuit prevention layer 99 having electrical insulation is interposed between the inner wall surface of the cylindrical side plate 92 in which the is accommodated. Examples of the method for forming the short-circuit prevention layer 99 include a method of coating the inner wall surface of the cylindrical side plate 92 with an insulating coat or the like. Alternatively, by covering the entire exposed portion of the positive electrode on the outer peripheral surface of the piezoelectric element unit 100 including the side surfaces of the positive electrode terminal plates 95 and 97 and the conductive layer 103 with a solidified product of insulating tape or insulating paste, It is also possible to form the short-circuit prevention layer 99.

Next, the structure of the main body of the ultrasonic transducer 81, the structure of the front plate 82, the backing plate 83, the side plate 92, and the joining relationship of these members will be described in detail.
The total length of the ultrasonic transducer 81 of the present embodiment is formed so as to substantially match the length of 1/2 wavelength or 3/2 wavelength of the resonance frequency of the ultrasonic transducer 81 (this embodiment). In the form, the total length of the ultrasonic transducer 81 is, for example, 31.3 mm).

  The front plate 82 that constitutes the distal end side of the ultrasonic transducer 81 includes a truncated cone part 82c in which the most advanced surface (for example, a small diameter part having a diameter of 5 mm) functions as the vibration radiation surface 93, and a large diameter part of the truncated cone part 82c ( For example, a cylindrical portion 82d having the same diameter as the diameter of 10 mm) and an insertion portion 82a in which a male screw 82b having a smaller diameter than the cylindrical portion 82d is formed are coupled along each axial direction (vibration axis). The vicinity of the rear end surface (base end surface) of the cylindrical portion 82d is a node position of the ultrasonic transducer 81 of the present embodiment. The insertion portion 82a in which the male screw 82b is formed on the peripheral surface constitutes a base end (rear end) portion of the front plate 82. The front plate 82 is not limited to the above-described shape, and for example, a plate having a columnar shape on the distal end side and a truncated cone shape on the proximal end side can be applied.

  Further, as shown in FIG. 10, the front plate 82 and the backing plate 83 have a cylindrical side plate 92 so as to sandwich the piezoelectric elements 88 to 91 disposed inside the cylindrical side plate 92. The insertion portions 82a and 83a are respectively inserted from the one and other opening portions 92a and 92b. Further, a peripheral edge 92 c in one opening portion 92 a of the cylindrical side plate 92 is screwed to the insertion portion 82 a of the front plate 82. That is, as shown in FIG. 10 (and FIG. 9), on the inner wall surface including the peripheral edge portion 92c of one opening portion 92a in the side plate 92, a female screw 92e to be fastened with the male screw 82b of the front plate 82 is formed. Yes.

  On the other hand, as shown in FIG. 9, the peripheral edge 92 d of the other opening 92 b of the cylindrical side plate 92 is caulked to the insertion portion 83 a of the backing plate 83. That is, as shown in FIGS. 8 to 10, the backing plate 83 is formed as a stepped columnar member, the rear end side (base end side) is configured by a small-diameter columnar portion 83 f, The distal end side (front plate 82 side) is composed of a large-diameter insertion portion 83a. For this reason, the insertion part 83a has a step part 83b including an edge part (corner part) 83e at a boundary part with the cylindrical part 83f. In addition, as shown in FIG. 10, the above-mentioned notch part 83d is formed in the outer shape part of the cylindrical part 83f. Further, the lead-out hole 83c is formed in the insertion portion 83a on the extension of the notch portion 83d.

  On the other hand, as shown in FIGS. 8 to 11, the peripheral portion 92 d in the other opening portion 92 b of the side plate 92 has a thin portion in which the cross section of the side plate 92 is thinner than other portions. (For example, a portion having a thickness of 0.2 mm protruding in a rib shape in the axial direction from the base end portion of the side plate 92) is provided.

  That is, as shown in FIG. 9, the piezoelectric element unit 100 having the piezoelectric elements 88 to 91 is surrounded (accommodated) by the side plate 92, and the front plate 82 (the last end surface of the insertion portion 82 a) and the backing plate 83 ( The thin portions 92f (opening portions 92b) of the side plate 92 in a state where the piezoelectric elements 88 to 91 sandwiched between the insertion portion 83a and the piezoelectric elements 88 to 91 are pressurized with a pressure adjusted within a specific pressure range. The edge portion 92d) is caulked by a step portion 83b including the edge portion 83e of the backing plate 83. Specifically, as shown in FIGS. 9 and 11, the thin-walled portion 92f encloses the edge portion 83e of the stepped portion 83b in the backing plate 83 so as to be inside the cylindrical side plate 92 (in the direction of arrow S1). Is bent (plastically deformed).

  Here, in the present embodiment, as shown in FIG. 9, screwing is exemplified as a joining structure between the insertion portion 82 a of the front plate 82 and one opening portion 92 a of the side plate 92. Welding may be applied. Further, the front plate 82 and the side plate 92 may be integrally formed as a single member. Further, by utilizing a joint structure similar to the screwing structure and the caulking structure described above, one opening portion 92a of the side plate 92 is caulked with respect to the front plate 82, and the other opening portion of the side plate 92 is provided. It is also possible to configure an ultrasonic vibrator having a structure in which 92b is screwed (or welded) to the backing plate 83.

  Next, a manufacturing method of the ultrasonic transducer 81 having such a structure will be described based on FIGS. 13 to 16 in addition to FIGS. Here, FIG. 13 is an exploded cross-sectional view of the caulking auxiliary device 120 used when manufacturing the ultrasonic transducer 81, and FIG. 14 shows the pressing member 131 constituting the caulking auxiliary device 120 of FIG. FIG. 15 is a cross-sectional view for explaining a caulking process using the caulking auxiliary device 120, and FIG. 16 is a diagram for explaining positioning accuracy required for the caulking auxiliary device 120.

  First, the structure of the caulking auxiliary device 120 will be described. As shown in FIGS. 13 to 15, the caulking auxiliary device 120 includes a base member 121, a guide member 125, and a pressing member 131. The base member 121 is installed on, for example, a work table in an environment where a caulking process is performed by caulking the side plate 92 to the backing plate 83. The base member 121 is configured as a stepped plate-like member, and includes a disk-like insertion convex portion 122 at the top. As shown in FIG. 15, the uppermost surface of the insertion convex portion 122 is an abutting surface 122 a against which the vibration radiation surface 93 of the ultrasonic transducer 81 is abutted.

  As shown in FIGS. 13 and 15, the guide member 125 has a cylindrical shape, and includes a small-diameter side plate positioning hole 126 and a large-diameter pressing member guide hole 127 that are coaxially drilled in the center portion. Have. The side plate positioning hole 126 is formed so as to be fitted to the outer diameter portion of the side plate 92 of the ultrasonic transducer 81 and the outer diameter portion of the insertion convex portion 122 of the base member 121. Further, the pressing member guide hole 127 has a hole diameter that is slidable with the outer diameter portion of the pressing member 131 formed in a cylindrical shape, and is a pressing member that is lowered in the direction of the arrow P1 when caulking as shown in FIG. The movement of 131 is guided (guided).

  As shown in FIGS. 13 to 15, the pressing member 131 is, for example, 45 with respect to the axial direction of the insertion hole 133 through which the lead wire 105 and the backing plate 83 are inserted, the backing plate positioning hole 132, and the ultrasonic transducer 81. And a caulking recess 134 having a pressing inclined surface 135 that is inclined. The backing plate positioning hole 132 is fitted to the outer peripheral surface of the cylindrical portion 83 f of the backing plate 83. As shown in FIGS. 14 and 15, the caulking recess 134 has the ultrasonic vibrator 81 set in the side plate positioning hole 126 of the guide member 125 mounted on the base member 121, and the pressing member guide hole 127. In the state where the pressing member 131 is inserted, the pressing inclined surface 135 and the thin portion 92f are annular grooves configured to face each other.

  That is, as shown in FIGS. 14 and 15, in the state where the ultrasonic vibrator 81 is set in the caulking auxiliary device 120, the pressing inclined surface 135 and the thin-walled portion 92f (the most proximal end portion) face each other, Further, when the pressing member 131 is lowered in the direction of the arrow P1, a pressing force is applied in a direction in which the pressing inclined surface 135 bends the thin portion 92f to the inside of the cylindrical side plate 92 (in the direction of the arrow S1). Done.

  Here, D1 in FIG. 16 indicates data when the thin portion 92f buckles when the pressing member 131 is lowered in the direction of the arrow P1, while D2 in FIG. 16 indicates the pressing member 131. Data is shown when the thin-walled portion 92f is appropriately bent in the direction of the arrow S1 so that the edge portion 83e of the stepped portion 83b of the backing plate 83 is rolled up when lowered in the direction of the arrow P1. In FIG. 16, it can be seen that the load with respect to the displacement of the pressing member 131 is temporarily relieved in the deformation process of the thin portion 92f. In addition, when buckling occurs, the increase in load with respect to the displacement is slightly increased.

  More specifically, the pressing member 131 is lowered in the direction of the arrow P1 in a state where the curved portion of the caulking concave portion 134 deviated from the pressing inclined surface 135 and the thin portion 92f (the most proximal end portion thereof) face each other. In this case, buckling of the thin-walled portion 92f occurs (the thin-walled portion 92f is not properly bent in the direction of the arrow S1), so that it is difficult to obtain a desired caulking strength. The base member 121, the guide member 125, and the pressing member 131 are formed with parts accuracy that can avoid such a situation.

Next, an actual manufacturing method of the ultrasonic transducer 81 using the above caulking auxiliary device 120 will be described.
First, while arranging the front plate 82 and the backing plate 83 at positions where the piezoelectric element unit 100 (piezoelectric devices 88 to 91) shown in FIG. A side plate 92 is arranged at a position surrounding the piezoelectric element unit 100 in cooperation with the reference numeral 83. Specifically, as shown in FIG. 10, the peripheral edge 92c in one opening portion 92a of the side plate 92 and the insertion portion 82a of the front plate 82 inserted into the side plate 92 from the one opening portion 92a. And screw. The piezoelectric element unit 100 is inserted (accommodated) into the cylindrical side plate 92 screwed to the front plate 82 from the other opening 92b. In this case, before accommodating the piezoelectric element unit 100, a short-circuit prevention layer 99 that electrically insulates the piezoelectric element unit 100 side from the side plate 92 side is formed in advance.

  Further, the insertion portion 83a of the backing plate 83 is inserted into the side plate 92 from the other opening 92b so that the piezoelectric element unit 100 inserted into the cylindrical side plate 92 is sandwiched between the insertion portion 82a of the front plate 82. Insert inside. At this time, the lead wire 105 connected to the piezoelectric element unit 100 is pulled out through the lead wire drawing hole 83c and the notch 83d of the backing plate 83.

  The ultrasonic transducer 81 (a semi-finished product) including the piezoelectric element unit 100, the front plate 82, the backing plate 83, and the side plate 92 assembled to each other in this way is, as shown in FIG. Set within 120. Next, using a device capable of applying a compressive stress such as a strength tester (autograph) or a press, for example, the pressing member 131 is uniaxially pressed in the direction of the arrow P1 at a constant speed (for example, 0.5 mm / min), and the backing is performed. The thin portion 92f of the side plate 92 is plastically deformed (caulked) in the direction of the arrow S1 so as to involve the edge portion 83e of the stepped portion 83b of the plate 83.

  In such a caulking step, ultrasonic caulking is applied in which the caulking portion (thin wall portion 92f) is plastically deformed by pressurization using ultrasonic vibration. By this ultrasonic caulking, the pressing force can be subdivided and efficiently transmitted to the thin portion 92f, so that a high caulking strength can be obtained. Further, in the caulking step, the clamping force applied to the piezoelectric elements 88 to 91 from the front plate 82 and the backing plate 83 is made variable (the distance in the axial direction of the backing plate 83 with respect to the front plate 82 is made variable), and the variation varies accordingly. The caulking is performed while monitoring the output from the piezoelectric element (for example, confirming the capacitance). That is, caulking is performed so that the position of the backing plate 83 is fixed at that position when a predetermined output value is obtained from the piezoelectric element.

  More specifically, the variable adjustment (capacitance adjustment) of the clamping force applied from the front plate 82 and the backing plate 83 side to the piezoelectric elements 88 to 91 is performed in order to obtain desired vibration characteristics from the ultrasonic transducer 81 main body. Done. That is, the ultrasonic transducer 81 has a resonance frequency that is physically determined mainly from its structure, and has the property of vibrating most efficiently when a drive signal corresponding to this resonance frequency is applied. The equivalent circuit in the vicinity of the resonance frequency is generally a series resonance circuit represented by a coil component (L), which is a characteristic of mechanical vibration, a resonance component due to a capacitor component (C), and a resistance component (R) representing a mechanical load. On the other hand, the braking capacitor portion (Cd) composed of the piezoelectric element unit 100 including the piezoelectric elements 88 to 91 and the positive and negative terminal plates 94 to 98 is represented in a connected form.

  Therefore, in the method of manufacturing the ultrasonic transducer 1 of the present embodiment, in order to drive the ultrasonic transducer 1 at the above-described resonance frequency, a braking capacitor portion (Cd) representing the capacitance of the ultrasonic transducer 1 is used. As tuning for adjusting to a predetermined design value, the clamping force applied to the piezoelectric element unit 100 is adjusted.

  As described above, in the ultrasonic transducer 81 of the present embodiment, the piezoelectric element unit 100 is housed in the front plate 82 and the side plate 92 previously assembled, and from this state, the piezoelectric elements 88 to 91 are twisted. Assembling can be completed by caulking the backing plate 83 to the side plate 92 without applying stress or the like. Therefore, according to the ultrasonic transducer 81, it is possible to assemble the piezoelectric element with an appropriate holding force while suppressing a positional deviation at the time of assembling the piezoelectric element, so that variation in vibration characteristics of the ultrasonic transducer can be suppressed. It is possible to suppress the application of relatively large mechanical stress to the piezoelectric element. Further, according to the ultrasonic transducer 81 of the present embodiment, unlike the first and third to fifth embodiments described above, a caulking ring or the like is unnecessary, so that the number of parts can be reduced and the process can be simplified. Can be planned.

  The present invention has been specifically described above with reference to the embodiments. However, the present invention is not limited to these embodiments, and various modifications can be made without departing from the scope of the invention. For example, in the embodiment using the caulking ring described above, a titanium alloy is exemplified as the constituent material of the front plate, the backing plate, and the side plate, but stainless steel or the like can also be applied as the constituent material. In the first to fifth embodiments except for the sixth embodiment, the node position (vibration node position) of the ultrasonic transducer has not been particularly described. Therefore, it is desirable to configure the ultrasonic transducer so that the caulking portion with low mechanical strength is at the node position.

The front view which shows the ultrasonic transducer | vibrator which concerns on the 1st Embodiment of this invention in a partial cross section. The figure which decomposes | disassembles and shows the one part component of the ultrasonic transducer | vibrator of FIG. The figure for demonstrating the manufacturing method of the ultrasonic transducer | vibrator of FIG. The front view which shows the ultrasonic transducer | vibrator which concerns on the 2nd Embodiment of this invention in a partial cross section. The front view which shows the ultrasonic transducer | vibrator which concerns on the 3rd Embodiment of this invention in a partial cross section. The front view which shows the ultrasonic transducer | vibrator which concerns on the 4th Embodiment of this invention in a partial cross section. The front view which shows the ultrasonic transducer | vibrator which concerns on the 5th Embodiment of this invention in a partial cross section. The disassembled perspective view of the ultrasonic transducer | vibrator which concerns on the 6th Embodiment of this invention. The front view which shows the ultrasonic transducer | vibrator of FIG. 8 in a partial cross section. The front view which decomposes | disassembles the ultrasonic transducer | vibrator of FIG. 9, and shows the part in a cross section. FIG. 11 is a detailed view of part A of the side plate shown in FIG. 10. Sectional drawing which shows the piezoelectric element unit incorporated in the ultrasonic transducer | vibrator of FIG. Sectional drawing which decomposes | disassembles and shows the auxiliary apparatus for crimping used at the time of manufacture of the ultrasonic transducer | vibrator of FIG. FIG. 14 is a detailed view of a B portion of the pressing member constituting the caulking auxiliary device in FIG. 13. Sectional drawing for demonstrating the caulking process using the auxiliary device for caulking of FIG. The figure for demonstrating the positioning precision requested | required of the auxiliary device for crimping of FIG.

Explanation of symbols

  1, 31, 41, 51, 71, 81 ... ultrasonic transducer, 2, 32, 42, 82 ... front plate, 2a, 82a ... front plate insertion portion, 2b, 3b, 32b, 33b ... root of the insertion portion 3, 33, 53, 83 ... backing plate, 3a, 83a ... insertion portion of backing plate, 5, 6 ... caulking ring, 7, 93 ... vibration radiation surface, 8, 9, 10, 11, 88, 89, 90, 91 ... Piezoelectric element, 12, 34, 92 ... Side plate, 12a, 12b, 92a, 92b ... Opening part, 12c, 12d ... Thin wall part, 28, 100 ... Piezoelectric element unit, 42a, 53a ... Cover part, 72 73 ... Buffer member, 74 ... Heat-shrinkable tube, 82b ... Male screw, 83b ... Stepped portion, 83e ... Edge portion, 92c, 92d ... Peripheral portion, 92e ... Female screw, 92f ... Thin-walled portion, 99 ... Short-circuit prevention layer.

Claims (14)

A piezoelectric element;
A pair of clamping members for clamping the piezoelectric element;
A cover member that is caulked to said pair of clamping member while surrounding the piezoelectric element in cooperation with the pair of clamping members,
Was immediately Bei,
The cover member is configured in a cylindrical shape, and the pair of sandwiching members are arranged such that one and the other of the cylindrical cover members sandwich the piezoelectric element disposed inside the cylindrical cover member. Each having an insertion portion inserted from each opening portion,
Furthermore, each peripheral part in each opening part of the said cylindrical cover member is crimped to each insertion part of the said pair of clamping member,
Ultrasonic transducer, wherein a call.   The ultrasonic transducer according to claim 1, wherein the caulking is performed in a state where the piezoelectric element is pressurized by the pair of clamping members. Each peripheral edge portion in each opening portion of the cover member is composed of a thin portion,
Each thin portion in each opening portion is caulked to a base portion of each insertion portion in the pair of clamping members,
The ultrasonic transducer according to claim 1 or 2, wherein   4. The ultrasonic transducer according to claim 3, wherein the cylindrical cover member is caulked through an annular locking member into which the peripheral edge portion of the cover member is inserted.   The ultrasonic transducer according to any one of claims 1 to 4, wherein the cover member and any one of the clamping members are configured as a single member.   The ultrasonic transducer according to claim 1, further comprising a buffer member fixed to at least one of the clamping members and having a hardness lower than that of the fixed clamping member. . Of said one and the other aperture prior Symbol cylindrical cover member, the peripheral edge portion of the opening portion of the one hand,
Instead of being caulked to the insertion part of the one clamping member, it is screwed or welded to the insertion part of the one clamping member ,
Ultrasonic transducer according to any one of claims 1, 2 and 6, characterized and this. The insertion portion of the other holding member includes a step portion,
A peripheral edge portion in the other opening portion of the cylindrical cover member is caulked to the stepped portion,
The ultrasonic transducer according to claim 7.   9. The caulking is performed in a state where the piezoelectric element sandwiched between the pair of sandwiching members is pressurized with a pressure adjusted within a specific pressure range. The ultrasonic transducer according to any one of the above. A member disposing step of disposing a cover member at a position surrounding the piezoelectric element in cooperation with the pair of sandwiching members while disposing the pair of sandwiching members at positions sandwiching the piezoelectric element from both sides;
And caulking the caulking step of the cover member to the pair of clamping member in a state where the piezoelectric element is pressurized through the pair of clamping members disposed in said member disposing step,
Have
The cover member is configured in a cylindrical shape, and the pair of sandwiching members are arranged such that one and the other of the cylindrical cover members sandwich the piezoelectric element disposed inside the cylindrical cover member. Each has an insertion part that can be inserted from each opening part,
Further, in the caulking step, the respective peripheral edge portions in the respective opening portions of the cylindrical cover member are caulked with respect to the insertion portions of the pair of clamping members respectively inserted into the cylindrical cover member. ,
A method of manufacturing an ultrasonic vibrator. A member disposing step of disposing a cover member at a position surrounding the piezoelectric element in cooperation with the pair of sandwiching members while disposing the pair of sandwiching members at positions sandwiching the piezoelectric element from both sides;
A caulking step of caulking the cover member to at least one of the pair of clamping members in a state where the piezoelectric element is pressurized through the pair of clamping members arranged in the member arranging step;
Have
The front Symbol cover member and one of said clamping member is constituted by a single member,
In the caulking step, caulking the component part of the cover member in one clamping member constituted by the single member with respect to the other clamping member;
Method for producing an ultrasonic oscillator you wherein a. A member disposing step of disposing a cover member at a position surrounding the piezoelectric element in cooperation with the pair of sandwiching members while disposing the pair of sandwiching members at positions sandwiching the piezoelectric element from both sides;
A caulking step of caulking the cover member to at least one of the pair of clamping members in a state where the piezoelectric element is pressurized through the pair of clamping members arranged in the member arranging step;
Have
Before SL cover member, together are configured in a cylindrical shape, the pair of clamping members, one and of said tubular cover member so as to sandwich the piezoelectric elements arranged on the inner side of said tubular cover member Each has an insertion part that can be inserted from the other opening part,
The member arranging step
Joining a peripheral edge portion of the one opening portion of the cover member and an insertion portion of one of the holding members in a state of being inserted into the cover member from the one opening portion by screwing or welding; ,
Inserting the piezoelectric element from the other opening into the cover member joined to the one clamping member;
The insertion part of the other holding member is inserted into the cover member from the other opening so that the piezoelectric element inserted into the cover member is inserted between the insertion part of the one holding member. And a process of
Have
Further, in the caulking step, the peripheral edge portion of the other opening portion of the cover member is caulked against the insertion portion of the other holding member inserted into the cylindrical cover member.
Method for producing an ultrasonic oscillator you wherein a.   The caulking process is characterized in that the caulking force applied to the piezoelectric element from the pair of clamping members is varied, and the caulking is performed while monitoring the output from the piezoelectric element that fluctuates accordingly. The method for manufacturing an ultrasonic transducer according to any one of 10 to 12.   14. The ultrasonic transducer according to claim 10, wherein in the caulking step, ultrasonic caulking is performed by plastic deformation of a caulked portion by pressurization using ultrasonic vibration. Method.

Images