JP4068239B2 - Ultrasonic transducer - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an ultrasonic transducer using a bimorph transducer, and more particularly to a mounting structure of an additional resonator for the bimorph transducer.
[0002]
[Prior art]
The structure of this type of conventional ultrasonic transducer will be described with reference to FIGS.
As shown in FIG. 4, the basic structure of an ultrasonic transducer using a bimorph vibrator is a circle in which a bimorph vibrator 3 in which a ceramic piezoelectric body 2 is bonded to a metal plate 1 is formed on the upper surface of a terminal plate 6. An elastic adhesive 11 is attached to the upper end of the circumferential convex portion, and electrode terminals 7 and 8 penetrating the terminal plate 6 are electrically connected to the electrodes of the metal plate 1 and the ceramic piezoelectric body 2, respectively. An additional resonator 4 is attached to the central portion of the metal plate 1 to form a composite vibrator 5, which is covered with a case 12 attached to a terminal plate 6.
By the way, the additional resonator 4 is formed in an inverted conical shape using aluminum as shown in FIG. 3, and a plating layer 13 is applied to the surface using a conductive material having good solderability, and the top of the lower end is formed by a bimorph vibrator 3 is fixed to the center of the upper surface of the metal plate 1 by soldering 14.
[0003]
[Problems to be solved by the invention]
However, the conventional soldering fixing has a problem that since the bonding area of the additional resonator to the metal plate is about 1 mm in diameter, the fixing strength is weak and the impact resistance is poor. In addition, since the joining area is small, there is a problem that the soldering operation is very difficult and the manufacturing cost such as labor costs is high.
The present invention was devised in view of these disadvantages, and greatly improves the bonding strength between the additional resonator and the metal plate, improves impact resistance and reliability, and facilitates the soldering operation. An object of the present invention is to provide an ultrasonic transducer capable of reducing the manufacturing cost.
[0004]
[Means for Solving the Problems]
In order to solve the above-described problems, the ultrasonic transducer according to the present invention has a hole in a bimorph vibrator in which a metal plate having a protrusion formed on an upper surface and a ceramic piezoelectric body are bonded to each other. An aluminum additional resonator plated with a conductive material having good solderability is attached to the protrusion of the metal plate and the hole of the additional resonator, and the metal plate and the additional resonator are connected to the protrusion of the metal plate. It is characterized in that it is fixed by soldering at a joint portion between the hole and the hole of the additional resonator.
[0005]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 and 2.
FIG. 1 is a partially cut-away front portion after joining showing the main part of an ultrasonic transducer according to an embodiment of the present invention, and FIG. It is a partially cutaway front view before joining which shows a part.
In FIG. 1 and FIG. 2, the same parts as those in FIG. 3 and FIG.
1 and 2, a plate-shaped ceramic piezoelectric body 2 having electrodes (not shown) formed on main surfaces facing each other and a plate-shaped metal plate 1 are bonded with an adhesive (not shown) or the like. In addition, the bimorph vibrator 3 is formed. The additional resonator 4 is formed in an inverted conical shape using aluminum, and a plating layer 13 is applied to the surface thereof using a conductive material having good solderability such as nickel. The additional resonator 4 has a hole 16 formed at the top of the lower end, and the metal plate 1 made of 36Ni—Fe alloy or the like of the bimorph vibrator 3 has a protrusion 15 formed at the center of the upper surface. The additional resonator 4 is placed on the metal plate 1 so that the hole 16 is aligned with the protrusion 15 of the metal plate 1 as shown in FIG. 2, and the hole 16 of the additional resonator 4 and the metal are connected as shown in FIG. The mating portion of the plate 1 with the protrusion 15 is fixed by soldering 14. At this time, the soldering operation can be performed from the upper surface of the additional resonator 4 and the workability is good, so that the manufacturing cost can be reduced.
As shown in FIG. 4, the bimorph vibrator 3 having the additional resonator 4 fixed as described above has an elastic adhesive such as silicon on the upper end of the circumferential convex portion formed on the upper surface of the terminal plate 6 which is an insulator. It is attached via the agent 11. Electrode terminals 7 and 8 penetrating the terminal plate 6 are electrically connected to the metal plate 1 of the bimorph vibrator 3 and the electrodes of the ceramic piezoelectric body 2, respectively. By housing these in the case 12, the ultrasonic transducer of the present invention is configured.
[0006]
【The invention's effect】
As described above, according to the ultrasonic transducer according to the present invention, the joint strength between the additional resonator and the metal plate can be greatly improved, and the soldering operation can be facilitated. Performance can be improved, and the manufacturing cost can be reduced.
[Brief description of the drawings]
FIG. 1 is a partially cutaway front view after joining showing a main part of an ultrasonic transducer according to an embodiment of the present invention.
FIG. 2 is a partially cutaway front view showing a main part of the ultrasonic transducer according to the embodiment of the present invention before joining.
FIG. 3 is a partially cutaway front view showing a main part of an ultrasonic transducer according to a conventional form.
FIG. 4 is a longitudinal sectional view showing the basic structure of an ultrasonic transducer.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Metal plate 2 Ceramic piezoelectric material 3 Bimorph vibrator 4 Additional resonator 5 Composite vibrator 6 Terminal board 7 Electrode terminal 8 Electrode terminal 9 Lead wire 10 Lead wire 11 Elastic adhesive 12 Case 13 Plating layer 14 Soldering 15 Protrusion 16 Hole

Claims (1)

In a bimorph vibrator made by bonding a metal plate and a ceramic piezoelectric material, the metal plate is provided with a protrusion at the center of the metal plate opposite to the ceramic piezoelectric material by pressing or the like, and a material with good solderability A hole is provided at the apex of a resonator formed in an inverted conical shape like a funnel made of plated aluminum, etc., and this resonator is combined with the protrusion on the metal surface of the bimorph vibrator, and these combination parts are fixed by soldering An ultrasonic transducer characterized by that.

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