JP4520317B2 - Ultrasonic probe, ultrasonic diagnostic device and ultrasonic flaw detector - Google Patents

Description

  The present invention relates to an ultrasonic probe used in medical fields such as diagnosis and treatment, and industrial fields such as non-destructive inspection, and an ultrasonic diagnostic apparatus and an ultrasonic flaw detection apparatus using the ultrasonic probe. .

  In recent years, an ultrasonic probe having a two-dimensional array of piezoelectric transducers is used to improve the image quality of an ultrasonic image using a technique such as dynamic focusing in the slice direction in addition to the scanning direction, or electronically. An apparatus that scans an ultrasonic beam three-dimensionally under control to create a three-dimensional ultrasonic image has been developed.

  As a configuration of an ultrasonic probe in which conventional piezoelectric vibrators are arranged two-dimensionally, it has been proposed how to ensure strength in order to prevent the collapse of minute piezoelectric vibrators arranged two-dimensionally in the manufacturing process. Yes. In manufacturing an ultrasonic probe in which piezoelectric transducers are two-dimensionally arranged, it is common to employ a method of dividing elements by machining using a dividing device such as a dicing saw when forming a two-dimensional array. It is necessary to withstand the processing load.

  FIG. 8 shows a cross-sectional view of a conventional ultrasonic probe. The ultrasonic probe shown in FIG. 8 has a configuration in which a plurality of piezoelectric vibrators 2 are arranged on a back load material 1. A hard auxiliary plate 3 is fixed to the surface of the back load material 1. A plurality of signal lines 4 are embedded in the back load material 1, one end of which is exposed on the surface of the hard auxiliary plate 3, and the electrode 5 of the piezoelectric vibrator 2 and the hard auxiliary plate 3 are connected to the conductive adhesive 6. The adhesive strength is increased by fixing the electrode 5 at the same time, and at the same time, the electrode 5 of the piezoelectric vibrator 2 and the signal line 4 are electrically connected (see, for example, Patent Document 1 below).

Further, in the conventional ultrasonic probe shown in FIG. 9, the hard auxiliary plate 3 in which the through hole 7 is provided in the central portion of the piezoelectric vibrator 2 is also formed on the electrode 5 side of the piezoelectric vibrator 2 so as to form the hard auxiliary plate. The three members are fixed to each other with the conductive adhesive 6 to further increase the adhesive strength (see, for example, Patent Document 2 below).
JP 2000-41299 (page 3, FIG. 3) JP 2003-9289 A (2nd page, FIG. 1)

  However, in the conventional ultrasonic probe described above, the hard auxiliary plate 3 is interposed between the piezoelectric vibrator 2 and the back load material 1 in the case of the configuration shown in FIG. The back load material 1 originally plays a role of improving the resolution by the damping effect and absorbing the ultrasonic wave radiated to the back load material 1 side, but the effect is not sufficiently exhibited by the intervention of the hard auxiliary plate 3. For this reason, the characteristics are deteriorated. In addition, when the acoustic impedance of the hard auxiliary plate 3 and the piezoelectric vibrator 2 or the back load material 1 cannot be matched, multiple reflections of ultrasonic waves at this interface portion occur. When used in an apparatus or the like, multiple noises appear on the diagnostic image, which may prevent accurate ultrasonic diagnosis.

  Further, in the case of the configuration shown in FIG. 9, another hard auxiliary plate 3 is interposed between the piezoelectric vibrator 2 and the back load material 1, so that the above problem is highly likely to become serious. . Further, increasing the overall height due to the increase in the number of the hard auxiliary plates 3 increases the risk of falling due to the processing load during the division processing of the piezoelectric vibrator 2, so that the effect of increasing the adhesive strength is achieved. It may be offset. Further, there is an adhesive layer (hereinafter referred to as an adhesive layer) for bonding the piezoelectric vibrator 2 and the back load material 1 as much as possible. It needs to be thin. Furthermore, in the case of an ultrasonic probe in which the piezoelectric vibrators 2 are arranged two-dimensionally, the variation in the thickness of the adhesive layer directly affects the variation in the characteristics of the piezoelectric vibrators 2. Desired.

  The present invention has been made in order to solve the above-mentioned conventional problems. The present invention achieves an improvement in adhesive strength without deteriorating the characteristics, and the characteristics of the piezoelectric vibrator vary depending on the thickness of the thin and uniform adhesive layer. It is another object of the present invention to provide an ultrasonic probe, an ultrasonic diagnostic apparatus using the ultrasonic probe, and an ultrasonic flaw detector.

In order to achieve the above object, an ultrasonic probe according to the present invention includes a plurality of piezoelectric vibrators for transmitting / receiving ultrasonic waves formed by dividing a piezoelectric vibrator, and a back surface of the piezoelectric vibrator. In an ultrasonic probe comprising a back surface load material provided on the side , an adhesive inflow groove is formed on the adhesive surface of the back surface load material with the piezoelectric vibrator in accordance with the position where the piezoelectric vibrator is divided. It is formed.

With this configuration, in the process of bonding the piezoelectric vibrator and the back load material, excess adhesive flows into the adhesive inflow groove, thereby forming a thin and uniform adhesive layer to realize a strong adhesive state. It is possible to suppress the deterioration of the characteristics of the piezoelectric vibrators constituting the ultrasonic probe and the variation of the characteristics of each piezoelectric vibrator. In addition, when a plurality of piezoelectric vibrators are formed by dividing the piezoelectric vibrator, the division position is divided according to the position of the adhesive inflow groove to form a piezoelectric vibrator array having an accurate shape. Can do.

  Moreover, the ultrasonic probe according to the present invention is characterized in that the width of the divided groove formed by dividing the piezoelectric vibrator is narrower than the width of the adhesive inflow groove.

  With this configuration, the adhesive strength between the piezoelectric vibrator and the back load material can be further increased.

  An ultrasonic diagnostic apparatus according to the present invention includes the above-described ultrasonic probe according to the present invention and an ultrasonic diagnostic apparatus main body electrically connected to the ultrasonic probe. .

  With this configuration, the ultrasonic probe according to the present invention can be used to perform highly accurate ultrasonic diagnosis.

  Furthermore, an ultrasonic flaw detector according to the present invention includes the above-described ultrasonic probe according to the present invention and an ultrasonic flaw detector main body electrically connected to the ultrasonic probe. .

  With this configuration, it is possible to perform highly accurate nondestructive inspection by using the advantages of the ultrasonic probe according to the present invention.

  An ultrasonic probe according to the present invention is an ultrasonic probe comprising a plurality of piezoelectric vibrators for transmitting and receiving ultrasonic waves, and a back load material provided on the back side of the piezoelectric vibrator, By forming an adhesive inflow groove on the adhesive surface of the back load material with the piezoelectric vibrator, excess adhesive flows into the adhesive inflow groove in the bonding process between the piezoelectric vibrator and the back load material. Can form a thin and uniform adhesive layer to realize a strong adhesive state, and suppress deterioration in characteristics of the piezoelectric vibrators constituting the ultrasonic probe and variations in characteristics among the piezoelectric vibrators. Can do.

  In addition, since the ultrasonic diagnostic apparatus according to the present invention uses the above-described ultrasonic probe, more accurate ultrasonic diagnosis can be performed.

  Furthermore, since the ultrasonic flaw detector according to the present invention uses the above-described ultrasonic probe, a more accurate nondestructive inspection can be performed.

Hereinafter, an ultrasonic probe according to an embodiment of the present invention will be described with reference to the drawings.
<First Embodiment>
FIG. 1 is a cross-sectional view showing the configuration of the ultrasonic probe according to the first embodiment of the present invention. In FIG. 1, an ultrasonic probe is arranged with piezoelectric vibrators 2 made of, for example, piezoelectric ceramics for converting an electrical input to generate ultrasonic waves or receiving received ultrasonic signals as electric signals. It has the structure made. The piezoelectric vibrator 2 is arranged on a back load material 1 made of an acoustic attenuation medium such as ferrite rubber, for example, and absorbs and attenuates ultrasonic waves transmitted to the back load material 1 side. The piezoelectric vibrator 2 has electrodes 5 on the upper and lower surfaces, and the lower electrode 5 is connected to a signal line 4 made of, for example, a printed board, a flexible printed board, or a thin metal plate, embedded in the back load material 1. Has been. The upper electrode 5 is commonly connected and grounded to a common electrode made of, for example, copper foil, but this is not shown in FIG.

  The adhesive inflow groove 8 is formed on the surface of the back surface load material 1 using a device capable of groove processing such as a dicing saw before the piezoelectric vibrator 2 is bonded onto the back surface load material 1. When the child 2 is bonded, the adhesive 9 flows. The dividing groove 10 is formed by a dividing device such as a dicing saw when forming the array of the piezoelectric vibrators 2. In FIG. 1, the forming position is aligned with the position of the adhesive inflow groove 8. In addition, as a configuration of the ultrasonic probe, an acoustic matching layer for efficiently transmitting and receiving ultrasonic waves and an acoustic lens for converging ultrasonic waves are attached to the upper surface of the piezoelectric vibrator 2, that is, the acoustic radiation surface side. There is also.

  Next, a method for creating this ultrasonic probe will be described with reference to FIGS. FIG. 2 shows a cross-sectional view of the back load material 1 in which the adhesive inflow groove 8 is formed. As shown in FIG. 2, the upper surface of the back load material 1 in which the signal lines 4 positioned according to the arrangement interval of the piezoelectric vibrators 2 of the ultrasonic probe are embedded, and the surface on which the piezoelectric vibrator arrangement is formed later. On the top, the adhesive inflow groove 8 is formed in advance using an apparatus capable of groove processing such as a dicing saw.

  Next, FIG. 3 is a cross-sectional view showing a state where the piezoelectric vibrator 2 is bonded onto the back load material 1. As shown in FIG. 3, when the piezoelectric vibrator 2 is bonded onto the back load material 1, an adhesive layer 11 is formed between the piezoelectric vibrator 2 and the back load material 1. Adhesive 9 flows into 8. In general bonding work, the adhesive is cured by applying pressure to the object to be bonded, but the viscosity of the adhesive temporarily decreases during the bonding process, and excess adhesive is removed by pressing. By doing so, a thin and uniform adhesive layer can be formed, and a strong adhesive state can be realized.

  The adhesive at the peripheral part of the adhesive easily escapes to the outside. However, the adhesive loses a place for evacuation near the center, making it difficult for the adhesive to escape compared to the peripheral part. On the other hand, in the ultrasonic probe according to the present embodiment, since the adhesive inflow groove 8 is formed in advance, excess adhesive 9 flows into the adhesive inflow groove 8. The thin and uniform adhesive layer 11 can be formed over the entire area 2 and a strong adhesive state can be realized. Furthermore, the wedge effect due to the adhesive 9 flowing into the adhesive inflow groove 8 further improves the adhesive strength.

  The adhesive 9 may be, for example, a conductive adhesive in which a silver filler is mixed in an epoxy adhesive, or an adhesive having no conductivity such as a simple epoxy adhesive. Absent. In the case of an adhesive having no electrical conductivity, the thickness of the adhesive layer 11 is made as thin as possible, so that the electrode 5 on the lower surface of the piezoelectric vibrator 2 and the signal line 4 are in direct contact with each other very locally. Ohmic contact that ensures a secure connection can be applied. In order to make the ohmic contact with the signal line 4 more reliable, a conductive film having a thickness of 1 μm or less that is not affected acoustically, such as a sputtered film, is connected to the signal line 4 on the back load material 1. It is also possible to realize ohmic contact between the conductive film and the electrode 5 of the piezoelectric vibrator 2.

  In the case of a conductive adhesive, since the adhesive layer 11 tends to be thin and the adhesive strength tends to be weak due to the inclusion of the conductive filler, it is conductive in the sense that the strength can be ensured without impairing the acoustic performance of the ultrasonic probe. It is better to adopt an ordinary adhesive that does not have any. The ultrasonic probe according to the present embodiment has a configuration that is particularly suitable when an ohmic contact is realized using an ordinary adhesive having no conductivity.

  Further, in the case of an ultrasonic probe in which strip-shaped piezoelectric vibrators 2 are arranged one-dimensionally, even if the thickness of the adhesive layer 11 is slightly uneven, the strip-shaped piezoelectric vibrator 2 and the back load material 1 In the case of an ultrasonic probe in which the piezoelectric vibrators 2 are two-dimensionally arranged, the thickness of the adhesive layer 11 between them becomes uneven and the degree of influence on the characteristics tends to be averaged. Therefore, when the thickness of the adhesive layer 11 is not uniform, the thickness of the adhesive layer 11 between each piezoelectric vibrator 2 and the back load material 1 is not uneven. It appears directly as a difference in thickness of the piezoelectric vibrators 2 and causes variations in characteristics between the piezoelectric vibrators 2. For this reason, the configuration of the ultrasonic probe according to the present embodiment is particularly suitable for an ultrasonic probe in which the piezoelectric vibrators 2 are two-dimensionally arranged.

  FIG. 4 is a cross-sectional view showing a process of dividing the piezoelectric vibrator 2 to form a piezoelectric vibrator array. The dicing saw 12 has a function of dividing the piezoelectric vibrator 2 to form a piezoelectric vibrator array.

  FIG. 5 is a top view showing a state in which the piezoelectric vibrator 2 is bonded onto the back load material 1 of FIG. As shown in FIG. 5, by making the size of the back load material 1 slightly larger than the size of the piezoelectric vibrator 2, the position of the adhesive inflow groove 8 can be visually recognized from above. As shown in FIG. 4, an adhesive inflow groove 8 is formed in advance at a position where the piezoelectric vibrator 2 is divided with an arrangement interval of the piezoelectric vibrators 2. The reason for this is that, in particular, in the case of an ultrasonic probe in which the piezoelectric vibrators 2 are two-dimensionally arranged, the position of the signal line 4 embedded in the back load material 1 is raised after the piezoelectric vibrator 2 is bonded. It is because it cannot visually recognize from. That is, since the position of the signal line 4 cannot be grasped when the piezoelectric vibrator 2 is divided, it is difficult to accurately form the array of the piezoelectric vibrators 2 by forming the dividing grooves 10 at accurate positions. It becomes.

  In the ultrasonic probe according to the present embodiment, the adhesive inflow groove 8 is formed in advance at a position where the piezoelectric vibrator 2 is divided, and the position of the adhesive inflow groove 8 is as shown in FIG. Since it can be visually recognized from above, the array of the piezoelectric vibrators 2 can be accurately formed by dividing the dicing saw 12 at the position.

  1 and 4 show the case where the depth of the dividing groove 10 is shallower than the depth of the adhesive inflow groove 8, but the present invention does not depart from the present invention even if the depth of the dividing groove 10 changes. Absent. 1 and 4 illustrate the case where the width of the dividing groove 10 is narrower than the width of the adhesive inflow groove 8. When the width of the dividing groove 10 is narrower, the adhesive 9 that has flowed into the adhesive inflow groove 8 remains, so that the effect of improving the adhesive strength due to the wedge effect can be expected. The width of the dividing groove 10 may be made wider than that of the adhesive inflow groove 8 as long as sufficient adhesive strength can be maintained by the realization.

  Further, in the present embodiment, the case where the adhesive inflow groove 8 and the dividing groove 10 are aligned and the adhesive inflow groove 8 is not formed other than the position of the dividing groove 10 has been described. The position, number, and shape of the adhesive inflow groove 8 can be changed within a range not impeding the performance of the touch element, and do not depart from the present invention.

<Second Embodiment>
Next, FIG. 6 is a schematic diagram showing an example of an ultrasonic diagnostic apparatus according to the present invention.
The ultrasonic diagnostic apparatus shown in FIG. 6 includes an ultrasonic diagnostic apparatus main body 13 and an ultrasonic probe 14 electrically connected thereto, and the ultrasonic probe 14 is the first of the present invention. The configuration of the ultrasonic probe according to one embodiment is provided.

  The operation of the ultrasonic diagnostic apparatus having the above configuration will be described. First, an operator (not shown) touches the ultrasonic transmission / reception surface of the ultrasonic probe 14 against the body surface of the subject 15. In this state, an electrical signal (drive signal) is transmitted from the ultrasound diagnostic apparatus main body 13 to the ultrasound probe 14. The drive signal is converted into ultrasonic waves by the piezoelectric vibrator in the ultrasonic probe 14 and transmitted to the subject 15. This ultrasonic wave is reflected in the body of the subject 15, and a part of the reflected wave is received by the piezoelectric vibrator in the ultrasonic probe 14 and converted into an electric signal (received signal) for ultrasonic diagnosis. Input to the apparatus body 13. The input received signal is subjected to signal processing in the ultrasonic diagnostic apparatus main body 13 and output as a tomographic image to a display device such as a CRT.

  In the ultrasonic diagnostic apparatus described above, as the ultrasonic probe 14, the ultrasonic probe of the present invention as described in the first embodiment is used. According to such an ultrasonic diagnostic apparatus, it is possible to perform highly accurate ultrasonic diagnosis by using the advantages of the ultrasonic probe described in the first embodiment.

<Third Embodiment>
Next, FIG. 7 shows a schematic diagram showing an example of an ultrasonic flaw detector according to the present invention.
The ultrasonic flaw detector shown in FIG. 7 includes an ultrasonic flaw detector main body 16 and an ultrasonic probe 14 that is electrically connected to the ultrasonic flaw detector main body 16. The ultrasonic probe 14 is the first of the present invention. The configuration of the ultrasonic probe according to one embodiment is provided.

  The operation of the ultrasonic flaw detector having the above-described configuration will be described. First, an operator (not shown) touches the ultrasonic transmission / reception surface of the ultrasonic probe 14 against the surface of the test object 17. In this state, an electrical signal (drive signal) is transmitted from the ultrasonic flaw detector main body 16 to the ultrasonic probe 14. The drive signal is converted into ultrasonic waves by the piezoelectric vibrator in the ultrasonic probe 14 and transmitted to the test object 17. This ultrasonic wave is reflected by scratches and defects inside the test object 17, and a part of the reflected wave is received by the piezoelectric vibrator in the ultrasonic probe 14 and converted into an electric signal (received signal). And input to the ultrasonic flaw detector main body 16. The input reception signal is signal-processed by the ultrasonic flaw detector main body 16 and displayed, for example, on a CRT as a tomographic image.

  In the ultrasonic flaw detector described above, as the ultrasonic probe 14, the ultrasonic probe of the present invention as described in the first embodiment is used. According to such an ultrasonic flaw detector, a highly accurate nondestructive inspection can be performed by taking advantage of the ultrasonic probe shown in the first embodiment.

  As described above, the ultrasonic probe according to the present invention includes an ultrasonic probe including a plurality of piezoelectric vibrators for transmitting and receiving ultrasonic waves and a back surface load material provided on the back side of the piezoelectric vibrator. In the child, an adhesive inflow groove is formed on the adhesive surface of the back load material with the piezoelectric vibrator, so that excess adhesive flows into the adhesive inflow groove in the bonding process between the piezoelectric vibrator and the back load material. By doing so, a thin and uniform adhesive layer can be formed to realize a strong adhesive state, and the deterioration of the characteristics of the piezoelectric vibrators constituting the ultrasonic probe and variations in the characteristics of each piezoelectric vibrator can be achieved. Therefore, the ultrasonic diagnostic apparatus using this ultrasonic probe has the effect of enabling accurate ultrasonic diagnosis, and is useful in the medical field such as diagnosis and treatment. Ultrasonic flaw detector using ultrasonic probe is non-destructive査 is useful in industrial fields such as.

Sectional drawing of the ultrasonic probe which concerns on the 1st Embodiment of this invention Sectional drawing of the back surface load material which formed the adhesive agent inflow groove | channel which comprises the ultrasonic probe which concerns on the 1st Embodiment of this invention Sectional drawing showing the state which adhered the piezoelectric vibrator on the back surface load material of the ultrasonic probe which concerns on the 1st Embodiment of this invention. Sectional drawing showing the process of dividing the piezoelectric vibrator of the ultrasonic probe which concerns on the 1st Embodiment of this invention, and forming a piezoelectric vibrator array The top view showing the state which adhered the piezoelectric vibrator on the back surface load material of the ultrasonic probe concerning a 1st embodiment of the present invention. Schematic which shows an example of the ultrasonic diagnosing device concerning the 2nd Embodiment of this invention. Schematic which shows an example of the ultrasonic flaw detector based on the 3rd Embodiment of this invention. Cross-sectional view of a conventional ultrasonic probe Cross-sectional view of another conventional ultrasonic probe

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Back load material 2 Piezoelectric vibrator 3 Hard auxiliary board 4 Signal line 5 Electrode 6 Conductive adhesive 7 Through-hole 8 Adhesive inflow groove 9 Adhesive 10 Dividing groove 11 Adhesive layer 12 Dicing saw 13 Ultrasonic diagnostic apparatus main body 14 Super Ultrasonic probe 15 Subject 16 Ultrasonic flaw detector main body 17 Test object

Claims (4)

In an ultrasonic probe comprising a plurality of piezoelectric vibrators for transmitting and receiving ultrasonic waves formed by dividing a piezoelectric vibrator, and a back load material provided on the back side of the piezoelectric vibrator,
An ultrasonic probe , wherein an adhesive inflow groove is formed on a bonding surface of the back load material with the piezoelectric vibrator in accordance with a position where the piezoelectric vibrator is divided . An ultrasonic probe according to claim 1, the width of the split groove formed by dividing the piezoelectric vibrator, and wherein the narrower than the width of the adhesive inflow groove. An ultrasonic probe according to claim 1 or 2, an ultrasonic diagnostic apparatus including the ultrasonic diagnostic apparatus main body in which the connected ultrasonic probe and electrically. An ultrasonic probe according to claim 1 or 2, ultrasonic flaw detector and an ultrasonic flaw detector body the connected ultrasonic probe and electrically.