JPH07327299A - Ultrasonic transducer - Google Patents

Abstract

PURPOSE:To make a connection without reducing the effective vibration area of a piezoelectric vibrator by adhering a printed board, a piezoelectric plate, and a conductive bump in electric contact with the piezoelectric vibrator. CONSTITUTION:The ultrasonic transducer 1 is constituted by adhering the flexible printed board 10 and piezoelectric ceramic (piezoelectric vibrator) 30 by using electric insulating resin, e.g. an epoxy adhesive 31, and the conductor (wiring pattern) of the flexible printed board 10 and the back driving electrode 33 of the piezoelectric ceramic 30 are connected electrically by the solder bump 13. Consequently, the flexible printed board 109 and piezoelectric ceramic 309 can be adhered without reducing the effective vibration area of the piezoelectric vibrator. Further, the flexible printed board 109 and piezoelectric ceramic 30 can be adhered through a constant adhering process without depending upon the vibrator shape.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic diagnostic apparatus for operating a subject by ultrasonic waves and detecting a reflected wave thereof to obtain a tomographic image. The present invention relates to an ultrasonic transducer that generates a sound wave.

[0002]

2. Description of the Related Art Conventionally, an ultrasonic diagnostic apparatus is known in which a body cavity of a subject is scanned with ultrasonic waves and a reflected wave thereof is detected to obtain a tomographic image of the body cavity.

As shown in FIG. 29, an ultrasonic diagnostic apparatus 100 is provided.
Is for transmitting and receiving ultrasonic waves by the ultrasonic probe 200 and displaying on the display device 300 based on the received ultrasonic waves, and is rapidly spreading because of the feature that it can be diagnosed in real time in a non-invasive manner.

The scanning is performed by mechanically moving an ultrasonic transducer provided in the ultrasonic probe 200, and electronic switching and ultrasonic transmission using an array transducer of the ultrasonic transducer. Although electronic scanning is performed by controlling the delay time, electronic scanning is predominant due to its maintainability and flexibility in diagnosis.

In addition, not only the diagnosis from the body surface but also the diagnosis area of the ultrasonic diagnostic apparatus is attempted by inserting an ultrasonic probe into the body cavity of the subject to obtain a good image from the body cavity. Internal ultrasonic probes have been developed. The diagnostic method of the ultrasonic diagnostic apparatus using the ultrasonic probe in the body cavity is not only ultrasonic tomographic image diagnosis (B-mode image diagnosis) but also Doppler diagnosis, color Doppler diagnosis, and the like. The same diagnostic method as the diagnosis is used. The ultrasonic diagnostic surface of the ultrasonic probe in the body cavity includes a linear tomographic plane that is a rectangular tomographic plane, a convex tomographic plane that is the insertion direction, and a radial tomographic plane that is orthogonal to the insertion axis. The surface is becoming mainstream.

In the above ultrasonic transducer by electronic scanning, as shown in FIG. 30, a bendable flexible printed board 210 and a piezoelectric ceramics (piezoelectric vibrator) 230 for ultrasonic vibration are electrically connected by a solder 213. ing. As a result, the piezoelectric ceramics 230,
It enables electrical connection with a control unit that controls ultrasonic transmission and reception.

Here, a conventional connecting method between the flexible printed board 210 and the piezoelectric ceramics (piezoelectric vibrator) 230 will be described with reference to a sectional view of a connecting portion between the flexible printed board 210 and the piezoelectric ceramics (piezoelectric vibrator) 230 shown in FIG. It demonstrates using.

A coverlay 215 made of a resin film such as polyimide is previously formed on the surface of the conductor (wiring pattern) 211.
Is bonded via an adhesive 217, and a base 219 made of a resin film such as polyimide is bonded to the back surface of the conductor (wiring pattern) 211 via the adhesive 217.
An insulating layer through hole is provided at a desired position of the cover lay 215 to expose the conductor 211, and thus the flexible printed board 210 provided with electrodes is prepared. On the other hand, the back drive electrode 23 is provided on the back surface of the piezoelectric ceramics (piezoelectric vibrator) 230.
3 and the front driving electrode 235 is formed on the front surface.

In this state, the electrodes of the flexible substrate 210 are connected to the ends of the back drive electrodes 233 of the piezoelectric ceramics 230 using solder 213. Then, the piezoelectric ceramics 230 are divided. Also, the front common electrode 235 of the piezoelectric ceramics 230 before or after the division.
The common electrode lead is connected to the predetermined position of (3) by solder or a conductive adhesive (not shown).

An electronic scanning type ultrasonic transducer for obtaining a convex tomographic plane or a radial tomographic plane is
After the flexible printed board 210 and the piezoelectric ceramics (piezoelectric vibrator) 230 are bonded as shown in FIG.
A backing material is adhered to the back drive electrode 233 of the piezoelectric ceramics 230, and the piezoelectric ceramics 230 are divided to form a vibrator array. After that, the vibrator array is bent into a desired arc shape and is fixed to a shape retaining member having a desired shape.

[0011]

However, in the conventional ultrasonic transducer, the piezoelectric ceramics 230
The flexible printed board 210 is attached to the rear drive electrode 233 of the
Are connected by solder 213, and the common electrode lead is connected to a predetermined position of the front common electrode 235 of the piezoelectric ceramics 230 by soldering or a conductive adhesive. There is a problem that the effective vibration area that can be used for transmitting and receiving ultrasonic waves of 230 becomes narrow.

Further, in the case of an ultrasonic transducer having a complicated shape, it is necessary to increase the connection area in order to maintain the bonding strength between the piezoelectric ceramics and the flexible printed board, which causes a problem that the effective area becomes small.

Furthermore, since the connection between the rear drive electrode 233 and the flexible printed board 210 and the connection between the front common electrode 235 and the common electrode lead are made only at the joint portion of the solder or the conductive adhesive, mechanical connection is required. There is a problem that the connection strength is insufficient, and damage to the connection portion is induced when the piezoelectric ceramic is divided. Especially, in the case of an electronic scanning ultrasonic transducer for obtaining a convex tomographic plane or a radial tomographic plane, if the radius of curvature is small,
There is a problem that the stress concentration at the connecting portion between the back surface drive electrode 233 and the flexible printed board 210 causes the detachment of the connecting portion and the cracking of the piezoelectric ceramics.

The present invention has been made in view of the above circumstances, and an object thereof is to connect a piezoelectric vibrator and a flexible printed board without reducing the effective vibration area of the piezoelectric vibrator, and An object of the present invention is to provide an ultrasonic transducer capable of preventing the disconnection.

[0015]

In order to achieve the above object, the present invention provides a piezoelectric plate constituting a piezoelectric vibrator having a polygonal shape or an arc shape, for example, a piezoelectric plate made of piezoelectric ceramics. Conductive bumps on the surface, such as metal,
Preferably, a printed board on which solder bumps are formed, for example, a flexible printed board, and the piezoelectric plate are electrically insulative adhesive such as a thermosetting adhesive in a state where the conductive bumps are in electrical contact with the piezoelectric vibrator. It is formed by adhering with an epoxy resin, and then the piezoelectric plate is divided for each piezoelectric vibrator. Further, a common electrode of each piezoelectric vibrator is extended to a side surface of the piezoelectric plate to form a common electrode joint portion,
A conductive plate is adhered to the side surface of the piezoelectric plate using a conductive adhesive, and the common electrode of each vibrator is electrically connected. Furthermore, when a member made of, for example, a rubber resin having flexibility is bonded to the back surface of the portion of the printed board corresponding to the piezoelectric plate and the piezoelectric plate is divided into the vibrators, the member having the flexibility. After dividing the inside or the printed board, the piezoelectric plate, the printed board and the flexible member are bent into a cylindrical shape. Further, after dividing the piezoelectric plate, the piezoelectric plate is inserted into a cylindrical bending jig to arrange the piezoelectric vibrators in a substantially cylindrical shape. Further, when the piezoelectric vibrator is bent into the cylindrical shape, the space at the center of the bending is filled with a resin, for example, a resin having acoustic characteristics similar to those of the bending material. Further, a base material, for example, metal, ceramics, glass or the like is arranged on the back surface of the printed board, the piezoelectric board is divided, and then the base material is removed from the printed board.

[0016]

According to the above configuration, the printed board having the conductive bumps formed on the surface corresponding to the piezoelectric vibrator of the piezoelectric plate constituting the piezoelectric vibrator and the piezoelectric plate have the conductive bumps. Adhesion is made in a state of being in electrical contact with the piezoelectric vibrator. Therefore, the piezoelectric vibrator and the flexible printed board can be connected without reducing the effective vibration area of the piezoelectric vibrator.

Since the common electrode of each piezoelectric vibrator is extended to the side surface of the piezoelectric plate to form a common electrode joint, and the conductive plate is bonded to the side surface of the piezoelectric plate using a conductive adhesive. , Each vibrator can be conducted.

Further, when a member having flexibility is adhered to the back surface of the portion of the printed board corresponding to the piezoelectric plate, and the piezoelectric plate is divided into the vibrators, the flexible member or even the printed board. After the division, the piezoelectric plate, the printed board, and the flexible member are bent into a cylindrical shape. This prevents the electrical connection between the printed board and the piezoelectric vibrator and the damage to the piezoelectric vibrator.

Further, after the piezoelectric plate is divided, the piezoelectric plate is inserted into a cylindrical bending jig to easily arrange the piezoelectric vibrators in a substantially cylindrical shape. Further, when the piezoelectric vibrator is bent into the cylindrical shape, the space at the center of the bending is filled with resin. This reduces acoustic reflection. Furthermore, after disposing the base material on the back surface of the printed board and dividing the piezoelectric board,
The base material is removed from the printed board. As a result, when the printed board is bent into a cylindrical shape, the bending diameter can be reduced.

[0020]

1 and 2 show a first embodiment of an ultrasonic transducer according to the present invention. FIG. 1 is a cross-sectional view of a bonded portion of a flexible printed board and a piezoelectric vibrator (piezoelectric ceramics) in a vibrator dividing direction, and FIG. 2 is a flexible printed board and a piezoelectric vibrator (piezoelectric ceramics).
It is sectional drawing of the array arrangement direction of the adhesion part with.

As shown in FIGS. 1 and 2, in the ultrasonic transducer 1 of the first embodiment, the flexible printed board 10 and the piezoelectric ceramics (piezoelectric vibrator) 30 are made of an electrically insulating resin such as an epoxy adhesive 31. Made by gluing,
Conductor (wiring pattern) 1 of the flexible printed board 10
1 and the back drive electrode 33 of the piezoelectric ceramics 30 are electrically connected by the solder bumps 13 described later.

Next, the structure of the flexible printed board 10 of the ultrasonic transducer 1 will be described with reference to FIG.

As shown in FIG. 3, a flexible printed board 10 has a conductor (wiring pattern) 11 on the surface of which a cover lay 15 made of a resin film such as polyimide is attached by an adhesive 1.
A base 19 made of a resin film such as polyimide is adhered to the back surface of the conductor 11 with an adhesive 17.

An insulating layer through hole 21 is formed at a desired position of the cover lay 15 so as to expose the surface of the conductor 11, and the insulating layer through hole 21 extends from the surface of the conductor 21 to the cover lay. Solder bumps 13 are provided so as to project up to 15 above. In addition, this solder bump 13
Is formed by melting solder into the insulating layer through hole 21 so as to protrude from the surface of the coverlay 15 by about 0.05 mm. In addition to solder, a metal such as Au or Cu may be used as long as it is a conductor.

As shown in FIG. 4, the wiring pattern (conductor) 11 of the flexible printed board 10 has a portion located on the piezoelectric ceramic 30 substantially parallel to the dividing direction of the piezoelectric ceramic 30, and the wiring pattern (when the piezoelectric ceramic 30 is divided) It is arranged so as to prevent the conductor 11 from being divided. The tip of the wiring pattern (conductor) 11 is provided with a circular bump forming position slightly larger than the diameter of the solder bump 13.

Next, the structure of the piezoelectric ceramic 30 of the ultrasonic transducer 1 will be described with reference to FIG.

As shown in FIG. 1, piezoelectric ceramics 30
Is the rear drive electrode 33 on the back surface and the front common electrode 35 on the front surface.
Is provided. By applying a voltage to the back drive electrode 33 and the front common electrode 35, the piezoelectric ceramics 3
0 starts ultrasonic vibration. Also, the front common electrode 35
Is bent to the side surface on the subject side, and the common electrode plate bonding surface 30
a is provided.

Next, a method of manufacturing the ultrasonic transducer 1 of the first embodiment will be described with reference to FIGS.

As shown in FIG. 1, the piezoelectric ceramics 30 having the rear drive electrode 33 and the front common electrode 35 formed thereon and the flexible printed board 10 having the wiring pattern (conductor) 11 formed thereon as shown in FIG. 4 are thermoset epoxy. Adhesive 3
1. Electrically and mechanically adhere to the desired position as shown in FIG.

Then, as shown in FIG. 6, a backing material 41 is attached to the back surface of the flexible printed board 10 (only the portion to which the piezoelectric ceramics 30 is adhered) to absorb the vibration to the back surface and prevent the vibration from continuing. . As the backing material 41, the flexible printed board 10 is used.
It is also possible to reduce the acoustic reflection on the flexible printed board 10 by using a rubber resin having an acoustic impedance substantially equal to. Further, a member having a small dimensional change may be used in order to enhance the manufacturability in the subsequent process. Further, it may have a structure in which a plurality of members are laminated in the thickness direction. Further, the backing material 41 may be an electrical insulator, and the flexible printed board 10 may be without the base 19 (a structure in which the conductor is exposed on the back surface).

Then, as shown in FIG. 7, the front common electrode 3
An acoustic matching layer 37 for efficiently transmitting ultrasonic vibration to the subject is provided on the surface 3. The acoustic matching layer 37 may have a multi-layer structure. Alternatively, the acoustic matching layer 37 made of resin may be applied and then polished.

Then, the transducer array is formed by cutting the components that have been subjected to the steps shown in FIG. 7 for each transducer as shown in FIG. 8 by a dicing device using a diamond blade.

At this time, in the example shown in FIG. 8, the dividing groove 43 is cut up to the upper part of the backing material 41, but as shown in FIG. 9, the dividing groove 43 is stopped up to the inside of the flexible printed board 10. May be. In this case, since the rubber backing material 41 is not cut, the workability of the cutting is improved.

After completion of the cutting, as shown in FIG. 10, a common electrode plate 45 made of a conductor, for example, a copper plate is adhered to the side surface of the subject side by using a conductive adhesive. At this time,
Since the common electrode plate bonding surface 30a is provided on the front common electrode 35, the common electrode plate 45 and the front common electrode 35 of the transducer array are electrically connected. As a result, the common electrode bonding surface 30a can be formed on the side surface of the subject side with a small area, so that the effective vibration area of the piezoelectric ceramics 30 can be increased as compared with the conventional ultrasonic transducer.

Then, the drive electrode lead-out lead (not shown) is electrically connected to the drive electrode lead-out pad (not shown) provided on the flexible printed board 10.

In this way, the ultrasonic transducer 1 of the first embodiment is manufactured.

As described above, in the ultrasonic transducer 1 of the first embodiment, the solder bumps 13 are formed at the predetermined positions of the flexible printed board 10, and the flexible printed board 1 is formed.
The surface of No. 0 and the piezoelectric ceramics 30 are bonded by an electrically insulating adhesive in a state where the solder bumps 13 are in electrical contact with the piezoelectric ceramics 30, so that the effective vibration area of the piezoelectric vibrator is not reduced. The flexible printed board 10 and the piezoelectric ceramics 30 can be bonded together. Furthermore, the flexible printed board 10 and the piezoelectric ceramics 30 can be bonded in a fixed bonding process without depending on the shape of the vibrator.

The ultrasonic transducer 1 of the first embodiment has been described by way of example with a circular transducer array. However, the present invention is not limited to this, and a polygon such as a pentagon or hexagon, or a half including an arc. Also applicable to circles, ellipses, etc.

FIG. 19 shows a second embodiment of the ultrasonic transducer according to the present invention.

FIG. 19 is an external view of an ultrasonic transducer in which vibrators are arranged in a substantially cylindrical shape.

Ultrasonic transducer 1-2 of the second embodiment
Is a flexible printed board 10 of the ultrasonic transducer 1 of the first embodiment, the flexible printed board 10 having the same structure as the piezoelectric ceramics 30, and the piezoelectric ceramics 30 are bent into a substantially cylindrical shape as shown in FIG. Planes and radial fault planes.

Next, a method of manufacturing the ultrasonic transducer 1-2 of the second embodiment will be described with reference to FIGS.

As shown in FIG. 1, a piezoelectric ceramics 30 having a rear drive electrode 33 and a front common electrode 35 formed thereon and a flexible printed board 10 having a wiring pattern (conductor) 11 formed thereon as shown in FIG. Then, it is electrically and mechanically bonded to a desired position as shown in FIG.

Then, as shown in FIG. 12, on the back surface of the flexible printed board 10 (only the portion to which the piezoelectric ceramics 30 is adhered), a flexible first board having a predetermined thickness is formed.
Backing material 41 of ultrasonic transducer 1 of the embodiment
A bending member 41a made of the same material as in 1 is bonded. Then, a member having mechanical stress and thermal stress equal to or lower than a predetermined value, for example, a base material 41b made of metal, ceramics, glass or the like is temporarily attached to the back surface of the bending material 41a by using a removable heat-melting wax, an adhesive or the like. . The bending material 41a and the base material 4
The backing material 41 is formed of 1b. In addition, the bending material 41
The backing material 41 may be adhered to the back surface of the flexible printed board 10 after the backing material 41 is formed by temporarily adhering a and the base material 41b using a heat-melting wax, an adhesive or the like.

Similar to the ultrasonic transducer 1 of the first embodiment, an acoustic matching layer 37 is provided on the front common electrode 33, as shown in FIGS. 13 and 14, and then cut to form a transducer array. Form. At this time,
Similar to the ultrasonic transducer 1 of the first embodiment, the dividing groove 43 may be stopped within the flexible printed board 10.

After the cutting is completed, the base material 41b is separated from the bending material 41a as shown in FIG. Then, what is completed up to the step shown in FIG. 15 is bent into a substantially cylindrical shape as shown in FIG.

In the conventional ultrasonic transducer, when it is bent into a substantially cylindrical shape, stress due to bending is concentrated in the soldering portion, resulting in contact failure and breakage of the piezoelectric ceramics in the vicinity of the soldering. In the ultrasonic transducer 1, the electric connection portion between the flexible printed board 10 and the piezoelectric ceramics 30 can be made as small as the solder bump 13.
It is possible to prevent the electrical connection failure and the damage of the piezoelectric ceramics 30, and it is possible to improve the manufacturing yield and the reliability.

Thereafter, as shown in FIG. 17, a substantially circular common electrode plate 45 made of a conductor, for example, a copper plate, is provided on the side surface of the subject side.
Are bonded using a conductive adhesive. At this time, since the common electrode plate bonding surface 30a is provided on the front common electrode 35, the common electrode plate 45 and the divided front common electrode 35 of the transducer array are electrically connected. In addition, the common electrode plate 45
As shown in FIG. 17, on the transducer array side of the central part of
The common electrode lead-out lead 47 is electrically connected and drawn out through the space of the central portion of the bending member 41a to the side facing the subject side (right side in the example of FIG. 17). Then, the space in the central portion is filled with resin. As the resin, a resin having acoustic characteristics similar to that of the bending material 41a is used. Therefore, acoustic reflection at the interface between the bending material 41a and the resin can be reduced. Further, if the resin having high mechanical strength is used, the mechanical strength of the ultrasonic transducer 1-2 can be increased.

Further, as shown in FIG. 18, the vibrator array may be bent by inserting it into a cylindrical bending jig 49. Then, the bending jig 49 is removed after bonding the common electrode plate 45 or after filling the space in the central portion of the bending member 41a with resin. In this case, bending can be easily performed. If a member that does not affect ultrasonic transmission is used as the bending jig 49, it need not be removed. Then, the bending jig 49 is adhered to the surface of the acoustic matching layer 37. In this case, bending and holding of the bent state can be easily performed.

Then, as shown in FIG. 19, the drive electrode lead-out lead 51 is electrically connected to the drive electrode lead-out pad (not shown) provided on the flexible printed board 10.

Thus, the substantially cylindrical ultrasonic transducer 1-2 of the second embodiment for obtaining the convex tomographic plane and the radial tomographic plane is manufactured.

As described above, the ultrasonic transducer 1-2 of the second embodiment electrically connects the surface of the flexible printed board 10 and the piezoelectric ceramics 30 with the solder bumps 13 electrically contacting the piezoelectric ceramics 30. Since they are adhered by an insulating adhesive, it is possible to prevent electrical connection failure and breakage of the piezoelectric ceramics 30 that occur during bending.

Next, a third embodiment of the ultrasonic transducer according to the present invention will be described.

In the transducer 1-3 of the third embodiment, a member having mechanical stress and thermal stress of not more than a predetermined value, for example, a base material 41b made of metal, ceramics, glass or the like is used as the backing material 41, and the flexible printed board 10 is used. Back surface (only the part where the piezoelectric ceramics 30 is bonded)
The ultrasonic transducer 1-2 has the same structure as the ultrasonic transducer 1-2 of the second embodiment shown in FIG.

Next, a method of manufacturing the ultrasonic transducer 1-3 of the third embodiment will be described with reference to FIGS.

As shown in FIG. 1, the piezoelectric ceramics 30 having the rear drive electrode 33 and the front common electrode 35 formed thereon and the flexible printed board 10 having the wiring pattern (conductor) 11 formed thereon as shown in FIG. 20. Then, it is electrically and mechanically bonded to a desired position as shown in FIG.

Then, as shown in FIG. 21, on the back surface of the flexible printed board 10 (only the portion to which the piezoelectric ceramics 30 is adhered), a member having mechanical stress and thermal stress below a predetermined value, such as metal, ceramics, glass, etc. The base material 41b using is temporarily adhered using a removable heat-melting wax, an adhesive or the like.

Then, similarly to the ultrasonic transducer 1 of the first embodiment, an acoustic matching layer 37 is provided on the front common electrode 33 as shown in FIGS. 22 and 23, and then cut to form a transducer array. Form. At this time,
The dividing groove 43 is stopped within the flexible printed board 10.

After the cutting is completed, the base material 41b is separated from the flexible printed board 10 as shown in FIG. Then, what is completed up to the step shown in FIG. 24 is bent into a substantially cylindrical shape as shown in FIG.

Thereafter, similar to the ultrasonic transducer 1-2 of the second embodiment, as shown in FIG. 26, a substantially circular common electrode plate 45 is adhered to the side surface of the subject side by using a conductive adhesive.

Further, the ultrasonic transducer 1-2 of the second embodiment is provided at the center of the common electrode plate 45 on the transducer array side.
Similarly, as shown in FIG. 26, the common electrode lead 47
Are electrically connected to each other, and are drawn out to the side facing the subject side (right side in the example of FIG. 26) through the space of the central portion of the flexible printed board 10. Then, the space in the central portion is filled with resin. As the resin, a resin having acoustic characteristics similar to those of the flexible printed board 10 is used. Therefore, acoustic reflection at the interface between the flexible printed board 10 and the resin can be reduced. Further, if the resin having a high mechanical strength is used, the mechanical strength of the ultrasonic transducer 1-3 can be increased.

Further, like the ultrasonic transducer 1-2 of the second embodiment, as shown in FIG. 27, the transducer array may be bent by inserting it into a cylindrical bending jig 49. .

Then, similarly to the ultrasonic transducer 1-2 of the second embodiment, as shown in FIG. 28, the drive electrode lead-out lead 51 is provided on the drive electrode lead-out pad (not shown) provided on the flexible printed board 10. To be electrically connected.

Thus, the substantially cylindrical ultrasonic transducer 1-3 of the third embodiment for obtaining the convex tomographic plane and the radial tomographic plane is manufactured.

As described above, in the ultrasonic transducer 1-3 of the third embodiment, as the backing material 41, a member having a mechanical stress and a thermal stress below a predetermined value, for example, a base material 41b made of metal, ceramics, glass or the like is used. Since it is temporarily attached to the back surface of the flexible printed board 10 in a detachable manner, not only the same effect as the ultrasonic transducer 1-2 of the second embodiment but also the ultrasonic transducer 1-2 of the second embodiment is used. Since it bends without using the used bending material 41a,
The bending diameter can be reduced, and an ultrasonic transducer with a smaller diameter can be realized.

[0066]

As described above, according to the present invention, the surface of the printed board having the conductive bumps formed on the surface corresponding to the piezoelectric vibrator of the piezoelectric plate and the piezoelectric plate are electrically connected to each other. Since the conductive bumps are adhered to the piezoelectric vibrator with an electrically insulating adhesive in a state of being in electrical contact with the piezoelectric vibrator, the piezoelectric vibrator and the flexible printed board are connected without reducing the effective vibration area of the piezoelectric vibrator. It is possible to prevent the disconnection.

Further, the common electrode of each piezoelectric vibrator is extended to the side surface of the piezoelectric plate to form a common electrode joint portion, and the conductive plate is adhered to the side surface of the piezoelectric plate using a conductive adhesive. Thus, the common electrode of each of the vibrators is made conductive, so that the common electrode bonding portion can be formed on the side surface of the subject side with a small area. Therefore, the effective vibration area of the piezoelectric vibrator can be increased.

Further, when the piezoelectric vibrator is divided, since the division is stopped within the printed board, the workability at the time of division is improved.

Further, the surface of the printed board having conductive bumps formed on the surface corresponding to the piezoelectric vibrator of the piezoelectric plate and the piezoelectric plate are electrically connected to the piezoelectric vibrator by the conductive bumps. When the piezoelectric plate is divided into the vibrators, the flexible member is adhered to the back surface of the portion of the printed board corresponding to the piezoelectric plate by an electrically insulating adhesive in a state of being in contact with the piezoelectric plate. Since the piezoelectric plate, the printed plate, and the flexible member are bent into a cylindrical shape after being divided into a member having a piezo or a printed board, a poor electrical connection between the printed board and the piezoelectric vibrator, and a piezoelectric vibrator It is possible to prevent the damage of the.

Furthermore, after the piezoelectric plate is divided, the piezoelectric plates are inserted into a cylindrical bending jig to arrange the piezoelectric vibrators in a substantially cylindrical shape, so that bending can be performed easily. .

Furthermore, when the piezoelectric vibrator is bent into the cylindrical shape, the space in the bending center is filled with resin,
Acoustic reflection can be reduced. Further, if the resin having high mechanical strength is used, the mechanical strength of the ultrasonic transducer can be increased.

Further, since the base material is arranged on the back surface of the printed board and the piezoelectric board is divided and the base material is removed from the printed board, when the piezoelectric board and the printed board are bent in a cylindrical shape, The bending diameter can be reduced.

[Brief description of drawings]

FIG. 1 is a cross-sectional view in a transducer dividing direction showing a first embodiment of an ultrasonic transducer according to the present invention.

FIG. 2 is a cross-sectional view in the array array direction showing the first embodiment of the ultrasonic transducer according to the present invention.

FIG. 3 is a cross-sectional view showing a structure of a flexible printed board.

FIG. 4 is an explanatory view showing a wiring pattern (conductor) of a flexible printed board.

FIG. 5 is an external view when a flexible printed board and piezoelectric ceramics are bonded (the ultrasonic transducer of the first embodiment).

FIG. 6 is an external view when a backing material is adhered to the back surface of the flexible printed board (the ultrasonic transducer of the first embodiment).

FIG. 7 is an external view when an acoustic matching layer is provided on the front common electrode (the ultrasonic transducer of the first embodiment).

FIG. 8 is an external view when the backing material is cut for each transducer (the ultrasonic transducer of the first embodiment).

FIG. 9 is an external view when the flexible printed board is cut for each transducer (the ultrasonic transducer of the first embodiment).

FIG. 10 is an external view when a common electrode plate is bonded to the side surface of the subject side (ultrasonic transducer of the first embodiment).

FIG. 11 is an external view when a flexible printed board and piezoelectric ceramics are bonded (the ultrasonic transducer of the second embodiment).

FIG. 12 is an external view when a backing material (bending material, base material) is adhered to the back surface of the flexible printed board (ultrasonic transducer of the second embodiment).

FIG. 13 is an external view when an acoustic matching layer is provided on the front common electrode (the ultrasonic transducer of the second embodiment).

FIG. 14 is an external view of a flexible printed board cut for each piezoelectric vibrator (the ultrasonic transducer of the second embodiment).

FIG. 15 is an external view when the base material is removed (the ultrasonic transducer of the second embodiment).

FIG. 16 is an external view when a flexible printed board, piezoelectric ceramics, etc. are bent into a substantially cylindrical shape (ultrasonic transducer of the second embodiment).

FIG. 17 is an external view when a common electrode plate is bonded to the side surface on the subject side (ultrasonic transducer of the second embodiment).

FIG. 18 is an external view when each transducer array is inserted into a cylindrical bending jig (ultrasonic transducer of the second embodiment).

FIG. 19 is an external view of the ultrasonic transducer of the second embodiment.

FIG. 20 is an external view when a flexible printed board and piezoelectric ceramics are bonded together (the ultrasonic transducer of the third embodiment).

FIG. 21 is an external view when a base material is bonded to the back surface of the flexible printed board (the ultrasonic transducer of the third embodiment).

FIG. 22 is an external view when an acoustic matching layer is provided on the front common electrode (the ultrasonic transducer of the third embodiment).

FIG. 23 is an external view of a flexible printed board cut for each piezoelectric vibrator (the ultrasonic transducer of the third embodiment).

FIG. 24 is an external view when the base material is removed (the ultrasonic transducer of the third embodiment).

FIG. 25 is an external view when a flexible printed board, piezoelectric ceramics, etc. are bent into a substantially cylindrical shape (the ultrasonic transducer of the third embodiment).

FIG. 26 is an external view when a common electrode plate is bonded to the side surface on the subject side (ultrasonic transducer of the second embodiment).

FIG. 27 is an external view when each transducer array is inserted in a cylindrical bending jig (the ultrasonic transducer of the third embodiment).

FIG. 28 is an external view of the ultrasonic transducer of the third embodiment.

FIG. 29 is a schematic view of an ultrasonic diagnostic apparatus.

FIG. 30 is a sectional view showing a conventional ultrasonic transducer.

[Explanation of symbols]

 1 Ultrasonic Transducer 10 Flexible Printed Board 11 Conductor, Wiring Pattern 13 Solder Bump 30 Piezoelectric Ceramics 30a Common Electrode Plate Bonding Surface 31 Epoxy Adhesive 33 Back Drive Electrode 35 Front Common Electrode 37 Acoustic Matching Layer 41 Backing Material 41a Bending Material 41b Base Material 43 division groove 45 common electrode plate 47 common electrode lead-out lead 49 bending jig 51 drive electrode lead-out lead

Claims (13)

[Claims] 1. A surface of a printed board having conductive bumps formed on the surface of a piezoelectric plate constituting a piezoelectric vibrator corresponding to the piezoelectric vibrator, and the piezoelectric plate, wherein the conductive bumps An ultrasonic transducer characterized by being bonded with an electrically insulating adhesive while being in electrical contact with a piezoelectric vibrator. 2. The surface of a printed board having conductive bumps formed on the surface corresponding to each piezoelectric vibrator of a piezoelectric plate constituting a plurality of piezoelectric vibrators, and the piezoelectric plate, the conductive bumps. The ultrasonic transducer is characterized in that, after being bonded to the piezoelectric vibrator with an electrically insulating adhesive while being in electrical contact with the piezoelectric vibrator, the piezoelectric plate is divided for each piezoelectric vibrator. 3. The common electrode of each of the piezoelectric vibrators is extended to a side surface of the piezoelectric plate to form a common electrode joint portion, and the conductive plate is bonded to the side surface of the piezoelectric plate using a conductive adhesive. The ultrasonic transducer according to claim 1 or 2, wherein the common electrode of each of the transducers is electrically connected by. 4. The ultrasonic transducer according to claim 1, wherein the piezoelectric vibrator has a polygonal shape. 5. The ultrasonic transducer according to claim 1, wherein the piezoelectric vibrator has a shape including an arc. 6. The ultrasonic transducer according to claim 1, wherein the piezoelectric vibrators are arranged in a substantially cylindrical shape. 7. The printed circuit board according to claim 1, wherein the printed circuit board is a flexible printed circuit board made of a wiring pattern which is a conductor and a bendable resin which covers the wiring pattern. Sonic transducer. 8. The division into the printed board when dividing the piezoelectric plate into each transducer.
7. The ultrasonic transducer according to any one of to 7. 9. A flexible member is adhered to a back surface of a portion of the printed board corresponding to the piezoelectric plate, and when the piezoelectric plate is divided into each vibrator, after dividing the flexible member into the flexible member. The ultrasonic transducer according to any one of claims 2 to 7, wherein the piezoelectric plate, the printed board, and a member having flexibility are bent. 10. A piezoelectric member is adhered to a back surface of a portion of the printed board corresponding to the piezoelectric plate, and when the piezoelectric plate is divided into each vibrator, the piezoelectric plate is divided into the inside of the printed board. 9. The ultrasonic transducer according to claim 2, wherein the plate, the printed board, and a member having flexibility are bent. 11. When disposing a base material on the back surface of the printed board and dividing the piezoelectric plate, after dividing into the printed board, the base material is removed from the printed board, and the piezoelectric plate and the printed board are further separated. 9. The ultrasonic transducer according to claim 2, wherein the ultrasonic transducer is bent. 12. The piezoelectric vibrator is arranged in a substantially cylindrical shape by inserting the piezoelectric plate into a cylindrical bending jig after dividing the piezoelectric plate. The ultrasonic transducer according to item 1. 13. The ultrasonic transducer according to claim 9, wherein when the piezoelectric vibrator is bent in a cylindrical shape, a resin is filled in a space of a bending center portion.