JPS61288699

Patent Translate
Powered by EPO and Google
Notice
This translation is machine-generated. It cannot be guaranteed that it is intelligible, accurate,
complete, reliable or fit for specific purposes. Critical decisions, such as commercially relevant or
financial decisions, should not be based on machine-translation output.
DESCRIPTION JPS61288699
[0001]
SUMMARY OF THE INVENTION The present invention forms a film having an acoustic
impedance close to that of a banking material or backing material in advance when joining the
banking material block to a piezoelectric element of an ultrasonic probe, and the abovementioned banking material block is formed thereon To provide an ultrasonic probe in which a
backing material or an adhesive is prevented from flowing into a cavity between piezoelectric
elements by bonding, and signal extraction bonding is performed via a thin film at a position
separated from the piezoelectric elements. It is a thing. BACKGROUND OF THE INVENTION 1.
Field of the Invention The present invention relates to an ultrasonic probe, and more particularly
to an ultrasonic probe in which a cavity between piezoelectric elements of an array type
ultrasonic probe is kept in an air layer. [Prior Art] As an ultrasonic probe of an ultrasonic
diagnostic apparatus widely used at present, a piezoelectric element is used as a vibrator, an
ultrasonic wave is oscillated, and the oscillation pulse is emitted to, for example, an in-vivo organ.
The reflected pulse reflected at the interface of different acoustic impedances in the organ is
received by the same vibrator, and a tomogram or the like of the organ is displayed on the
display 2 . The ultrasonic probe used in such an ultrasonic diagnostic apparatus is configured
as shown in FIGS. 6 and 7. FIG. 6 is a side sectional view of a part of the conventional ultrasonic
probe, and FIG. 7 is a sectional view taken along the line AA 'of FIG. Reference numeral 1 denotes
a piezoelectric element made of PzT, barium titanate or the like which becomes a probe. As
shown in FIG. 6, a plurality of belts are arranged in parallel. Electrodes 4 and 5 are formed at
both ends of the piezoelectric element, and matching layers 2. A backing material block 3 is
formed. The backing material 3a in the cavity 7 is processed in vacuum so that no bubbles are
generated in the backing material when the backing material is poured into the cavity 7 between
the piezoelectric elements 1.1------ There is a problem that unnecessary vibration is transmitted
to the adjacent piezoelectric element through the clogged banking material 3a to deteriorate the
01-05-2019
1
characteristics. In order to solve such a problem, one having an ultrasonic probe as shown in FIG.
8 has been proposed. That is, in the side sectional view of FIG. 8, the same parts as in FIG. 6 and
FIG. The backing material block 3 is formed in advance, and the backing material block 3 is
bonded to the electrode 5 side of the piezoelectric element 1 with the adhesive 8. In this way, the
backing is formed in the divided cavity 7 between the elements It is possible to prevent the
harmful effect of filling the material. [Problems to be Solved by the Invention] In the structure
shown in FIG. 8 described above, there occurs an adverse effect that the adhesive 8 flows into the
space 7 to cause the cross 1--ray characteristic deterioration between the piezoelectric elements.
Also, as shown in FIGS. 6 to 8, in order to solder the signal line 6 to the surface of the Ll
piezoelectric element or to solder the flexible printed board, stress is generated in the connecting
portion when the piezoelectric element vibrates. There is a disadvantage in that the connection
between the signal line and the piezoelectric element is deteriorated and the mass of the
connection portion is further increased by solder, and unnecessary reflection from the
connection portion is also generated. Also after attaching the backing to the piezoelectric
element. In the case of dividing the element, signal lines must be provided from the piezoelectric
element in advance, which requires precise alignment. [Means for Solving the Problems] The
present invention has been made in view of the above-mentioned drawbacks, and its first object
is to completely fill the cavities between a plurality of piezoelectric elements with only air, A
second object of the present invention is to provide an ultrasonic probe in which the signal line
lead-out portion is not at the bottom of the piezoelectric element electrode but at a position away
from the piezoelectric element. Then, the means is provided with a matching layer on one of the
electrodes formed at both ends of a plurality of piezoelectric elements juxtaposed in an array
type, and a preparatory film having an acoustic impedance close to that of the backing material
or the other on the other. When bonding a banking material block to the preliminary film via an
adhesive, a space formed by the thickness of the preliminary film and the cut width of the cavity
formed between the plurality of piezoelectric elements arranged in parallel in an array type The
sum of the volumes is selected to be larger than the amount of the adhesive flowing into the
cavity. This is achieved by an ultrasound probe characterized by [Operation] In the ultrasonic
probe of the present invention, an adhesive is formed in advance before forming a backing
material block which is formed on the side opposite to the radiation surface when the
piezoelectric elements are divided to obtain a plurality of arrayed probes. Structure that allows
the flow of the adhesive and allows the bonding of the electrode at a distance from the
piezoelectric element while absorbing the flow of the adhesive by selecting the relationship
between the thickness of the preliminary film and the cut width of the cavity The Embodiment 1
An embodiment for providing a cavity between piezoelectric elements of an ultrasonic probe
according to the present invention and bonding an electrode and a signal at a position separated
from the piezoelectric element is shown in FIG. This will be described with reference to the
drawings. FIG. 1 is a partial side sectional view of the ultrasonic probe of the present invention.
FIG. 2 is a perspective view for explaining the first step of polishing the ultrasonic probe
01-05-2019
2
according to the present invention, and FIG. 3 is a sectional view taken along line 13-B 'in FIG.
Sectional view of 4 is a cross-sectional view for explaining the third step similar to FIG. 3, and
FIG. 5 is a view on arrow C of FIG. In FIG. 1, 1 (, 1 piezoelectric element 4.5 圓: electrodes formed
on both sides of the piezoelectric element 1, 9 is formed of an insulator by a frame, and formed
to be laminated to the electrodes 4 and 5 ′ ′ The thick signal extraction electrode 10.11 is a
frame 9 "binary extension.
A matching layer 2 is formed on the signal extraction electrode 11 on the radiation side, and on
the signal extraction electrode 10 on the side on which the backing material block 3 is formed, a
banking material or a backing material is formed in a frame 12 formed as necessary. The H
charges having substantially the same acoustic impedance are injected and fixed. Alternatively,
the preliminary coating 13 is formed by attaching a sheet of rice cake. (In this case, the frame 12
is unnecessary). Next, the backing material block 3 is bonded onto the preliminary membrane 13
via an adhesive. A side plate 14.15 is a backing plate (from the side of the signal extraction
electrode 10 of Ill, the signal line 6 is extracted from the position away from the piezoelectric
element 1 as shown by the broken line. Further, a signal can be obtained from the signal
extraction electrode 16 on the matching layer 2 side through the metal foil 16.17. The steps for
obtaining the ultrasonic probe having the above-described configuration will be described with
reference to FIG. First, as shown in FIG. 2, a hollow frame 9 is formed of an insulator so that the
rectangular piezoelectric element 1 can enter through the small air gap 18, and the piezoelectric
element 1 is bonded to the hollow part of the frame 9. Insert fixed via agent. As indicated by the
broken line in FIG. 2 of the frame 9, rod-like members 9a and 9b made of an insulator in the
same manner as the frame may be adhered to the left and right sides of the piezoelectric element
with an adhesive. When the agent overflows, the adhesive is removed by polishing, and the
electrodes 4.5 formed on both sides of the piezoelectric element 1 may be formed again by
sputtering or the like. Thus, a thin film is formed by sputtering on the surface 19.20 shown in
FIG. 3 of the piezoelectric element to which the frame 9 or the rod-like members 9a and 9b are
fixed, and then a thick conductive film is formed on the thin film by plating. The signal extraction
electrode is set to 10.11. Next, as shown in FIG. 3, the matching layer 2 is attached on the
electrode 11 on the radiation surface side of the piezoelectric element 1. The matching N2 may
be a two or more layer matching as needed. Next, as shown in FIG. 4, a rectangular frame 12
larger than at least the rectangular piezoelectric element 1 is disposed on the signal extraction
electrode 10 and adhered and fixed. In this case, the height H of the frame 12 is selected to be
several hundred microns and is set to, for example, about 3200 microns. The backing material
13 may be poured into the frame 12 or several hundreds of membranes 13 having an acoustic
impedance substantially equal to that of the backing material may be applied, in which case the
frame 12 is not necessary. In the present invention, the backing material or the acoustic
impedance of the backing material poured into the frame 12 described above is defined as the
preliminary film 13 including a film substantially equal to the banking material, and is described
as one preliminary film in the present invention. Next, as shown in FIG. 5 which is a view on
01-05-2019
3
arrow C of FIG. 4, the preliminary film 13.1 is formed in the direction orthogonal to the
longitudinal direction of the piezoelectric element 1.
Signal extraction electrode 10, 11 ° frame 9. The piezoelectric element 1 is cut by a slicing
machine to form a grooved portion as a cavity 7 as an array element. This grooving is cut to a
position where alignment N2 is reached. Next, as shown in FIG. 1, the banking material block 3
previously fixed with the banking material is fixedly joined with the adhesive 21 on the
preliminary membrane 13. At this time, by controlling the amount of the adhesive 21 to be stuck
on the preliminary film 13 and setting the protrusion of the adhesive 21 as shown in FIG. 5, the
height H of the preliminary film 13 and the notch G of the cavity 7 The piezoelectric element 1
can be limited to only the adhesive 22 that has run out inside. Between 1 and 1 can be a cavity 7
of air only. That is, between the thickness H of the preliminary film I3 and the plurality of
piezoelectric elements arranged in parallel in the array type. H may be selected so that the
product HXG of the cut width G of the cavity 7 formed in 1-----is equal to or greater than the
thickness of the adhesive of the backing layer. In this way, the amount of the adhesive 22 flowing
into the incision of the empty piece 7 in the adhesive 21 is absorbed by the preliminary
membrane 13. Also, with regard to the adhesion of the side plate 14.15 shown in FIG. 1, since
the piezoelectric element 1 is separated because the frame 9 is present, the adhesive does not
protrude to the kerf of the piezoelectric element -10- It is easy. Further, in FIG. 1, a thin film is
controlled and attached on the preliminary film 13 so that the adhesive does not protrude to the
piezoelectric element side, and a banking material is poured into the space surrounded by the
side plate 14 ° 15 and the thin film. You may want to harden it. The signal line may be taken
out by forming a groove in the side plate 14 indicated by the broken line in FIG. 1 for the signal
on the backing material side and inserting the signal line. Then, a junction with the signal line is
formed at a position away from the piezoelectric element, that is, at the end of the signal
extraction electrode 10. Similarly, on the side of the signal extraction electrode 11 on the
radiation side, a joint is formed at the end of the metal foil 9. Since the present invention is
configured as a trapezoid, it is possible to keep the cavity of the piezoelectric element part
completely in a hollow state and to provide the piezoelectric element without extracting the
signal under the piezoelectric element. It is possible not only to reduce the influence but also to
provide an ultrasonic probe having many features, such as the choice of the acoustic impedance
of the banking material freely.
[0002]
Brief description of the drawings
[0003]
01-05-2019
4
FIG. 1 is a side sectional view of an ultrasonic probe according to the present invention.
FIG. 2 is a perspective view showing the process of performing the ultrasonic probe of the
present invention. FIG. 3 is a cross-sectional view along the line B--B 'in FIG. FIG. 4 is a crosssectional view similar to FIG. 3 for explaining another process of the ultrasonic probe of the
present invention. FIG. 5 is a partially enlarged cross-sectional view showing a further step of the
eyebrow viewed from the C direction of FIG. 4; FIG. 6 is a side sectional view of a conventional
ultrasonic probe. 7 is a sectional view taken along the line 1-A 'in FIG. FIG. 8 is a side sectional
view of another example showing a conventional ultrasonic probe. ■ · · Piezoelectric element. 2Matching layer. 3 ... banking material block. 4.5 .. electrode. 6 ··· Signal line. 7 ... hollow part. 8.21
... adhesive. 9.12 ... Frame. 9a, 9b ... rod-like members. 10.11. Signal extraction electrode. 13 ...
preliminary membrane. 14.15 ... side plate. 16.17 ... metal foil. 18 ... void. 19.20 ... face.
01-05-2019
5