JPH04314000A - Linear array ultrasonic wave probe - Google Patents

Abstract

PURPOSE:To simply check a wide range of a reagent at a high speed by uniformizing check sensitivity between unit probes in a linear array ultrasonic wave probe comprising plural unit probes. CONSTITUTION:A vibrator 25 integrated with each unit probe is made of a piezoelectric high polymer material. Since lateral vibration and shear vibration or the like are not almost caused in the piezoelectric high polymer material, the length of each unit probe is set long and the check area of the entire linear array ultrasonic wave probe 22 is set wide. Moreover, even when the thickness of the adhesives in existence to each of electrode plates 24, 26 and a matching layer 27 and between the matching layers 27 is fluctuated between the unit probes, the detection sensitivity between the unit probes is controlled almost constant.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention uses an electronic scanning ultrasonic inspection device to scan a wide range of a subject at high speed.
The present invention relates to a linear array ultrasonic probe formed by linearly arranging a plurality of unit probes.

0002

BACKGROUND OF THE INVENTION By using an ultrasonic probe, it is possible to easily detect defects in steel materials and measure plate thickness. If the object to be inspected, such as steel, has a large area,
By using a linear array ultrasonic probe consisting of multiple unit probes arranged in a straight line and an electronic scanning ultrasonic inspection device, defects can be detected and plate thickness can be detected quickly over a wide range of the surface of the specimen. Can perform measurements. In other words, since the unit probes to be excited in the linear array ultrasonic probe are simply switched electrically in order, the inspection speed is lower than when the probes are moved mechanically. can rise significantly.

[0003] This linear array ultrasonic probe has a method that focuses or deflects the ultrasonic waves output from the transducer of each unit probe by changing the timing of excitation of the transducer of each unit probe. There are linear array ultrasonic probes in which the length of each transducer is set short in order to scan a wide range, and linear array ultrasonic probes in which the length of each transducer is set long in order to scan a wide range.

A linear array ultrasonic probe in which the length of the transducer of the unit probe is set to be long is constructed as shown in FIG. 7, for example. That is, the linear array ultrasonic probe 1 has a plurality of unit probes 2 arranged in a straight line, and the unit probes 2 are connected to each other by, for example, adhesive.

In each unit probe 2, a vibrator 8 whose both sides are sandwiched between electrode plates 6 and 7 is placed between a matching layer 4 and a back layer 5 which are in contact with a test object 3 such as a steel plate. It is intervening. A ground wire 10 and a signal wire 11 are connected from the electronic scanning ultrasonic inspection device 9 to each electrode plate 6, 7 of each unit probe 2, respectively.

[0006] The electronic scanning ultrasonic inspection device 9 includes at least one pulse generator and a receiving circuit, and each unit probe 2 constituting the linear array ultrasonic probe 1 has a built-in pulse generator and a receiving circuit. A pulse signal is sent to each electrode plate 6, 7 in order, and each ultrasonic wave is made to enter the subject 3 from each vibrator 8. Each reflected wave of the ultrasonic waves reflected from a defect or the bottom surface of the object 3 is received by the transducer 8, converted into an electric signal, and input to a receiving circuit in the electronic scanning ultrasonic inspection apparatus 9. Therefore, this receiving circuit confirms each defect position and bottom surface position from the echo included in each received signal.

In this way, the linear array ultrasonic probe 1
By using the electronic scanning ultrasonic inspection device 9, the presence or absence of defects and the presence or absence of defects can be detected over a wide range of the object 3 without moving the position of the linear array ultrasonic probe 1 attached to the object 3. It becomes possible to measure the position and the distance (plate thickness) to the bottom surface in a short time.

[0008]

However, the linear array ultrasonic probe 1 as shown in FIG. 7 still has the following problems to be solved.

That is, in an inspection method in which a pulse signal is sequentially applied to each unit probe 2 constituting the linear array ultrasonic probe 1 using an electronic scanning ultrasonic inspection apparatus 9 and echoes are observed, Naturally, each unit probe 2 constituting the linear array ultrasonic probe 1 needs to have the same detection sensitivity characteristics.

However, as shown in the figure, each unit probe 2
is composed of a matching layer 4, an electrode plate 6, a vibrator 8, an electrode plate 9, and a back layer 5. When these are assembled into one unit probe 2, an epoxy adhesive is used to fix each electrode 6, 7 to the matching layer 4 and back layer 5. On the other hand, piezoelectric ceramics are generally used as the vibrator 8. The acoustic impedance of this piezoelectric ceramic is, for example, about 30×10 6 Kg/m 2 s. On the other hand, the acoustic impedance of epoxy adhesive is, for example, about 3.0×106 Kg/m2 s,
Comparing the two, there is a difference of about 10 times. As a result, the ultrasonic waves are reflected by the adhesive layer, and the transmitted or received ultrasonic waveform is disturbed.

Therefore, it is necessary to adjust the influence of each adhesive layer on each unit probe 2 to the same conditions. Therefore,
It is necessary to set the thickness of the adhesive to be uniform and thin over all unit probes 2. However, it is very difficult to make the thickness of the adhesive layer in each unit probe 2 uniform over all unit probes 2 due to manufacturing technology. As a result, it is difficult to control the detection sensitivity and frequency characteristics of each unit probe 2 to constant values.

[0012] In order to eliminate such inconveniences, a method of manufacturing a linear array ultrasonic probe in which the unit probe length is short is effective. That is, JP-A-55-743
This is the linear array ultrasonic probe 12 shown in FIG. 8(a) shown in Japanese Patent No. 00.

In this linear array ultrasonic probe 12, first, a back layer 13 having a shape equal to the overall shape of this linear array ultrasonic probe 12, and an electrode plate 14 having a shape equal to this back layer 13. , piezoelectric ceramics (vibrator)
15, electrode plate 16, and matching layer 17 are assembled using the above-mentioned ordinary epoxy adhesive. After the epoxy adhesive solidifies, piezoelectric ceramics (
A notch 18 reaching up to the transducer (vibrator) 15 is made to form a unit probe as shown.

In the integrated linear array ultrasonic probe 12 constructed as described above, the process of applying the epoxy adhesive is performed only once, so it can be determined that the epoxy adhesive is applied to a uniform thickness. Therefore, the thickness of the epoxy adhesive in each unit probe divided by the notch 18 can be considered to be uniform over all unit probes. Therefore, Figure 7
The problems of the linear array ultrasonic probe 1 shown in can be solved.

However, in each of the linear array ultrasonic probes 1 and 12 shown in FIGS. 8(a) and 7,
Since each unit probe has a rectangular shape, each transducer 8
, 15 vibrates not only in the original thickness direction, but also in the horizontal direction (lateral direction), or slides in the lateral direction. Therefore, vibrations in directions other than the thickness direction have an adverse effect on vibrations in the thickness direction, so the wave number of the ultrasonic pulse increases, the temporal resolution deteriorates, and the spatial resolution of defects in the direction of ultrasonic propagation decreases.

The first method for suppressing such vibrations in the horizontal direction (lateral direction) is to increase the ratio of the length of the transducer in the direction perpendicular to the direction in which the probes are arranged, the length in the arrangement direction, and the thickness. The key is to select the optimal value. However, in this case, it is difficult to manufacture a probe having an arbitrary size at an arbitrary frequency.

As a second method for suppressing vibration, a linear array ultrasonic probe 1 as shown in FIG. 8(b) is used.
9 has been proposed (Japanese Unexamined Patent Publication No. 63-209634). In this linear array ultrasonic probe 19, in addition to the above-mentioned notches 18, a large number of sub-cuts 21 are formed between each notch 18 in order to suppress vibrations in the horizontal direction. However, as shown in FIG. 8(b), forming a large number of notches 18 and 21 complicates the overall configuration of the linear array ultrasonic probe 19, increases manufacturing costs, and reduces the degree of freedom in design. be restricted.

Furthermore, in the above-mentioned integrated linear array ultrasonic probe, the maximum length of each unit probe currently developed is about 3 mm. If the length of each unit probe is short, it is necessary to increase the number of channels (number of unit probes) in order to scan a wide range, which complicates the overall configuration of the linear array ultrasonic probe. hand,
Manufacturing costs will increase significantly.

In addition, when manufacturing a new linear array ultrasonic probe, in addition to the dimensional restrictions on each unit probe as described above, the design is complicated, and the development cost and development period are There are concerns that the situation will be prolonged.

The present invention was made in view of the above circumstances, and it is possible to expand the inspection area of each unit probe with a simple configuration, and to inspect a wide area of the object with a small number of unit probes. An object of the present invention is to provide a linear array ultrasonic probe that can scan a wide range of a subject at high speed with a small number of channels when combined with an electronic scanning ultrasonic inspection device.

[0021]

[Means for Solving the Problems] In order to solve the above problems, a linear array ultrasonic probe in which a plurality of unit probes of the present invention are arranged in a straight line is made of a piezoelectric polymer material. a single transducer plate; a plurality of electrode plates arranged linearly on the upper surface of the transducer plate and corresponding to each unit probe; and a back layer that commonly covers the upper surface of each electrode plate; This device includes one common electrode plate attached to the lower surface of the vibrator plate, and a matching layer attached to the lower surface of this common electrode plate.

[0022] In another invention, in addition to each means in the linear array ultrasonic probe of the invention described above,
An acoustic wedge made of a polymeric material is attached to the lower surface of the matching layer.

In still another invention, the unit probes constituting the linear array ultrasonic probe are arranged in a plurality of rows. Furthermore, the unit probes are arranged with a predetermined distance offset from each other in each row, which is smaller than the interval between the unit probes. In order to achieve this, a single transducer plate made of a piezoelectric polymer material is used, and each row is shifted in a straight line by a predetermined distance less than the unit probe spacing between each row. A plurality of electrode plates arranged on the top surface of the transducer plate and corresponding to each unit probe, a back layer covering the top surface of each electrode plate, and one common electrode plate attached to the bottom surface of the transducer plate. and a matching layer attached to the lower surface of the common electrode plate.

Furthermore, in another invention, each unit probe constituting the linear array ultrasonic probe is attached to a transducer plate made of a piezoelectric polymer material and to the upper surface of the transducer plate. a first electrode plate attached to the oscillator plate; a back layer attached to the upper surface of the first electrode plate; a second electrode plate attached to the lower surface of the vibrator plate; It consists of an attached matching layer.

[0025]

[Operation] In the linear array ultrasonic probe constructed as described above, a piezoelectric polymer material is used as the vibrator. The acoustic impedance of this piezoelectric polymer material is approximately 4.51×10 6 Kg/m 2 s, which is approximately the same as the acoustic impedance of the epoxy adhesive described above. Therefore, even if the thickness of the adhesive layer varies somewhat between unit probes, the effect on each unit probe will be approximately the same. That is, it is possible to absorb variations in working accuracy between the unit probes due to the bonding process.

Furthermore, since the piezoelectric polymer material has a smaller elastic modulus than conventional piezoelectric ceramics, unnecessary vibrations such as lateral vibrations and shear vibrations hardly occur. Therefore, it is possible to set each unit probe in an arbitrary shape without requiring a large number of cuts as shown in FIG. 8(b). Therefore, a unit probe with a wide inspection area can be easily realized.

Furthermore, as described above, piezoelectric polymer materials hardly generate lateral vibrations, shear vibrations, etc. other than the original vibrations in the thickness direction. Therefore, since it has almost no effect on the horizontally adjacent unit probes, the transducer plate made of this piezoelectric polymer material can be used for all unit probes without dividing it into individual unit probes. It is possible to use one common vibrator plate throughout.

As a result, the electrode plate and matching layer located on the subject side of this vibrator plate can be formed of one electrode and matching layer without being divided. That is, manufacturing costs can be reduced, and variations in detection accuracy caused by dimensional accuracy between unit probes can be suppressed.

Furthermore, the unit probes constituting the linear array ultrasonic probe are arranged in a plurality of rows, and the unit probes are shifted between each row by a predetermined distance smaller than the unit probe spacing. are arranged.

Since the ultrasonic beam transmitted by each unit probe is narrow, the defect detection sensitivity at the positions between the ultrasonic beams is reduced. Therefore, generally, a plurality of unit probes are excited simultaneously. However, in the present invention, as described above, the position of each unit probe is shifted for each row, and the probes are arranged in multiple rows. Therefore, even if the ultrasonic beams that are transmitted at the same timing are formed using only one unit probe, the decrease in defect detection sensitivity between the ultrasonic beams is compensated for by the unit probes arranged in other rows. be able to. Therefore, a wider range can be detected with a smaller number of unit probes.

[0031]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic diagram showing the general configuration of a linear array ultrasonic probe according to an embodiment. The linear array ultrasonic probe 22 of this embodiment is composed of 32 unit probes arranged in a straight line.

In FIG. 1, the width of each unit probe is 6 mm.
The length is 4 mm. Therefore, the total size is 6
It has a shape of mm x 128 mm. A single common electrode plate 26 is attached to the upper surface of the matching layer 27, the lower surface of which is in contact with the subject 3, using, for example, an epoxy adhesive. One vibrator plate 25 is attached above the common electrode plate 26 so as to cover the common electrode plate 26. The vibrator plate 25 is made of a piezoelectric polymer material represented by, for example, P (VDF-TrFE).

Thirty-two electrode plates 24 corresponding to each unit probe are attached linearly to the upper surface of the vibrator plate 25 at minute intervals using, for example, an epoxy adhesive. Each electrode plate 24 is made of a copper plate and has a shape of 6 mm in width and 4 mm in length. A back layer 23 is attached so as to commonly cover the upper surface of each of the 32 electrode plates 24. The back layer 23 is made of Bakelite, for example, and has a thickness of:
This is 1/4 of the wavelength λ of the ultrasonic waves used in this linear array probe 22.

FIG. 2 shows this linear array ultrasonic probe 2.
2 is a block diagram showing a schematic configuration of an electronic scanning ultrasonic inspection device 28 in the case of detecting a defect present in an object 3 such as a steel plate using the electronic scanning ultrasonic inspection device 2 and the electronic scanning ultrasonic inspection device 28. FIG.

This electronic scanning ultrasonic inspection apparatus 28 includes 32 pulse generators 29, 32 amplifiers 30 and 32 detectors 31 as receiving circuits. Each channel from number 1 to number 32 is shown in Figure 1.
Each unit probe 32 of the linear array ultrasonic probe 22 is individually connected. The scanning channel control device 33 is
A plurality of channels to be excited simultaneously are selected and a drive signal is sent to each corresponding selected pulse generator 29 via the pulse generator control circuit 34. Each selected pulse generator 29 outputs a pulse signal based on the drive signal.

The pulse signal output from the pulse generator 29 is applied between the electrode plate 24 and the common electrode plate 26 in the unit probe 32 of the corresponding channel of the linear array ultrasonic probe 22. As a result, the portion of the transducer plate 25 sandwiched between the corresponding electrode plate 24 and the common electrode plate 26 vibrates, generating pulsed ultrasonic waves, which are incident on the subject 3 via the matching layer 27. Ru. The pulsed ultrasonic waves incident into the object 3 are reflected by defects existing inside or on the surface, are received as echoes by the transducer plate 25, and are converted into electrical signals, which are then transmitted to the electronic scanning ultrasonic inspection device 28. The signal is input to the amplifier 30 of the corresponding channel.

The received signal amplified by the amplifier 30 is envelope-detected by the next detector 31. The envelope detection signal is input to the received wave synthesizer 35. The received wave synthesizer 35 first synthesizes each detected waveform of the envelope detection signal output from the detector 31 of each channel specified by the scanning channel control unit 33, that is, each echo waveform corresponding to a defect. It is sent to the received wave display section 36. A received wave display 36 made of, for example, a CRT display device displays each echo waveform caused by the input defect. Next, three unit probes 32
The control procedure of the scanning channel control section 33 will be explained using an example of simultaneous excitation and simultaneous reception.

First, the three pulse generators 29 numbered 1 to 3 are selected, and the first unit probe 32 to the third unit probe 32 of the linear array ultrasonic probe 22 are selected. Pulsed ultrasonic waves are output from the three unit probes 32 at the same timing. Then, the received wave combiner 35 combines the echoes output from the three detectors 31 from the first detector 31 to the third detector 31, and displays the synthesized echo on the received wave display section 36. The above is the first ultrasonic transmission/reception process.

Next, the three pulse generators 29 numbered 2 to 4 are selected, and the second unit probe 32 to the fourth unit probe 32 of the linear array ultrasonic probe 22 are selected. Pulsed ultrasonic waves are output from the three unit probes 33 at the same timing. Then, the received wave combiner 35 combines the echoes output from the three detectors 31 from the second detector 31 to the fourth detector 31, and displays the result on the received wave display section 36. The above is the second ultrasound transmission/reception process.

In this way, while using three channels simultaneously, the channels are selected by shifting one channel at a time. As a result, the output for a total of 30 scanning lines is displayed on the received wave display section 36 using 32 channels.

The reason why the three unit probes 32 are simultaneously excited and received will now be explained. That is, since the ultrasonic beam transmitted by one unit probe 32 is thin, the defect detection sensitivity at the positions between the ultrasonic beams decreases, and there is a possibility that defects may be overlooked. In addition, when several or more unit probes 32 are excited simultaneously, the vibration area that forms the ultrasonic beam becomes wider, which reduces the accuracy of detecting the defect location and forms an ultrasonic beam suitable for flaw detection. Can not.

Note that if the distance between the unit probes is shortened, an appropriate ultrasonic beam can be formed even when several or more unit probes 32 are excited simultaneously, but the total number of unit probes If they are equal, the overall width of the linear array ultrasonic probe 22 becomes narrow, making it impossible to detect defects over a wide area at once. Therefore, the number of unit probes 32 that simultaneously excite and simultaneously receive to form one ultrasonic beam is 2 to 2.
4 is optimal.

FIG. 3(a) shows a steel pipe 37 with an outer diameter of 219.1 mm and a wall thickness of 8.2 mm, parallel to the tube axis and with an ultrasonic refraction angle of 45 mm as shown in FIG. 3(b). Acoustic wedge 38 made of polymeric material such as acrylic so that
FIG. 3 is a perspective view showing a case where a linear array ultrasonic probe 22 is attached to the outer circumferential surface of the steel pipe 37 to perform flaw detection. Incidentally, the angle θ of the acoustic wedge 38 is determined by the following equation from Snell's law. θ=sin-1(sin 45°/3230×2730
) (However, 3230 is the sound velocity of transverse waves in steel pipes, and 2730 is the sound velocity of longitudinal waves in acrylic. Unit: m/s)

[0045]
The scanning line switching time is set to 250 μsec. Therefore, the time required for measurement processing for all 30 scanning lines is 7.5 msec. Then, a through hole with an outer diameter of 3.2 mm was intentionally made in the steel pipe 37, and this through hole was inspected using the linear array ultrasonic probe 22 and the electronic scanning ultrasonic inspection device 28 of the embodiment. The results are shown in Figure 4.

FIG. 4 is a diagram in which the linear array probe 22 was moved in the tube axis direction and the detection sensitivity of each scanning line was measured. The overall detection sensitivity of the linear array ultrasonic probe 22 is the envelope characteristic of each unit probe 32 from No. 1 to No. 32 constituting the linear array ultrasonic probe 22. The difference between the highest value and the lowest value in this envelope characteristic is 3 dB at maximum. This 3 dB difference is almost negligible when compared to the overall detection sensitivity, so by using the linear array ultrasonic probe 22 of the embodiment, a range of 128 mm in the pipe axis direction of the steel pipe 37 can be detected by 7 dB. 5 mse
Flaw detection can be performed at a high speed of c. FIG. 5 is a perspective view showing a linear array ultrasound probe according to another embodiment of the present invention.

Linear array ultrasonic probe 4 of this embodiment
0 is composed of a total of 32 unit probes 41 arranged linearly in two rows. Each unit probe 41 is 1
It has a size of 0 mm x 10 mm, and since 16 unit probes 41 are arranged in one row, the width of the entire linear array ultrasonic probe 40 is 160 mm. As shown in the figure, each unit probe 41 in the second row from No. 17 to No. 32 is connected to one from No. 1 to No. 16.
Compared to each unit probe 41 in the row, the array is shifted by 5 mm, which is half the distance between the unit probes.

[0048] Then, one sheet of the above-mentioned P(VD
A single common electrode plate 43 having the same shape is attached to the lower surface of a vibrator plate 42 made of a piezoelectric polymer material (F-TrFE). Furthermore, a matching layer 44 having the same shape is attached to the lower surface of this common electrode plate 43. On the other hand, 32 electrode plates 45 corresponding to each unit probe 41 are attached to the upper surface of the diaphragm 42. A back layer 46 made of Bakelite is attached to the upper surface of each electrode plate 45.

In the manufacturing process, first, each electrode plate 45 and each back layer 46 are formed into one plate. Next, the electrode plate 45 is divided into 32 pieces by forming notches 47 in the electrode plate 45 through an etching process, and then the lower surface of the electrode plate 45 and the upper surface of the vibrator plate 42 are bonded together. Each unit probe 41 is formed.

[0050] Such a linear array ultrasonic probe 40
When performing flaw detection on a test object using the ultrasonic beam, the ultrasonic beam is formed by one unit probe 41. That is, the ultrasonic beam is equivalent to an ultrasonic beam transmitted from a single type ultrasonic probe measuring 10 mm x 10 mm. Electronic scanning is performed while electrically switching between transmitting and receiving probes one by one. First, flaw detection is performed by transmitting and receiving ultrasonic waves using the unit probe 41 shown in FIG.

[0051] Next, No. 2, No. 3, ..., No. 16, No. 17,
..., No. 31, and No. 32, the unit probes 41 that transmit and receive ultrasonic waves are switched in order for flaw detection. therefore,
The number of ultrasonic beams is 32 in total. Since the scanning line switching time was set to 250 μs, the time required for measurement processing using all 32 unit probes 41 was approximately 8 ms.
It is.

FIG. 6 shows the vertical flaw detection of the linear array ultrasonic probe 40 shown in FIG. FIG. 3 is a diagram showing the relationship between the arrangement direction (electronic scanning direction) and the mechanical scanning direction.

Generally, in such an arrangement, if flaw detection is performed only with each unit probe 41 in the first row, for example, the portion located between the ultrasonic beams of adjacent unit probes 41 will be damaged. There are cases where flaw detection sensitivity decreases and defects cannot be detected. Therefore, like the linear array ultrasonic probe of the embodiment, by arranging the unit probes 41 in two rows with their positions shifted by half the width of the unit probes, 1
Defects missed in the measurement of the first row can be reliably detected in the second row of measurements.

In this way, in the linear array ultrasonic probe 40 shown in FIG. 5, even if the ultrasonic beam is formed by one unit probe 41, defects can be reliably detected without being overlooked. . Therefore, a wide range can be detected with a small number of channels.

As described above, in the linear array ultrasonic probes 22, 40 of the present invention, each unit probe 32, 41
As each vibrator, one vibrator plate 25, 4 made of a piezoelectric polymer material and having the same shape as the matching layers 27, 44 is used.
2 is used. As mentioned above, piezoelectric polymer materials have a smaller elastic modulus than conventional piezoelectric ceramics, so unnecessary vibrations such as lateral vibrations and shear vibrations hardly occur. Therefore, since there is no need for a large number of cuts as shown in FIG. 8(b), it is possible to set each unit probe 32, 41 in an arbitrary shape. Therefore, the linear array ultrasonic probes 22, 4 with a wide inspection area
0 can be easily achieved. In particular, even a linear array ultrasonic probe 40 having a somewhat complicated two-row configuration as shown in FIG. 5 can be easily manufactured.

Furthermore, since the vibrator plates 25 and 42, the common electrode plates 26 and 43, and the matching layers 27 and 44 are each composed of one plate or layer, the manufacturing process is simplified;
Compared to the conventional linear array ultrasonic probes 1, 12, and 19 shown in FIGS. 7 and 8, manufacturing costs can be significantly reduced.

[0057] The acoustic impedance of the piezoelectric polymer material is determined by interposing the piezoelectric polymer material between each electrode plate 24, 45 and the back layer 23, 46 and between the common electrode plate 26, 43 and the matching layer 27, 44. Compared to the acoustic impedance of epoxy adhesive, the difference is not that great. Therefore, even if the thickness of the adhesive layer of the epoxy adhesive varies somewhat between the unit probes 32, 41, the effect on each unit probe 32, 41 will be substantially the same. That is, when manufacturing the linear array ultrasonic probes 22, 40, each unit probe 32, 41 is removed by the bonding process.
It is possible to absorb variations in work accuracy between each other. Therefore, manufacturing efficiency can be improved.

It should be noted that the present invention is not limited to the embodiments described above. In the embodiment, a P(VDF-TrFE) piezoelectric polymer material is used as the vibrator of the unit probe 32, but other types of piezoelectric polymer materials may be used.

In addition, in the embodiment, each unit probe 3
As a method of dividing the electrode plate 24 into 2 pieces, the electrode plate 24 to be adhered on the back layer 23 was divided into 32 pieces. For example, as shown in FIG. The second electrode plate, the vibrator plate made of piezoelectric polymer material, the first electrode, and the back layer are laminated in order, and each is manufactured independently, and later they are arranged in a linear manner. Good too. Further, the number of arrays of each unit probe 41 in the linear array ultrasound probe 40 of FIG. 5 is not limited to two rows, but may be three or more rows.

[0060]

[Effects of the Invention] As explained above, according to the present invention,
The vibrator making up each unit probe is made of piezoelectric polymer material. Since this piezoelectric polymer material hardly generates lateral vibrations or shear vibrations, it is possible to set the length of each unit probe longer, and the inspection area of the entire linear array ultrasonic probe can be set wider. . As a result, by combining it with an electronic scanning ultrasonic inspection device, it becomes possible to inspect a wide range of the object at high speed even with a small number of channels, and the efficiency of testing work can be greatly improved.

Furthermore, even if the thickness of the adhesive present between each electrode plate and the matching layer varies between unit probes, the detection sensitivity between the unit probes remains almost constant. can be controlled. Therefore, the detection accuracy of the entire linear array ultrasonic probe can be improved.

Furthermore, even if an acoustic wedge made of a polymeric material is attached to the matching layer, the ultrasonic wave will not be reflected attenuated or the waveform will be deformed at the interface between the acoustic wedge and the matching layer, so it will not be easy to change the beveled angle. An ultrasonic probe can be constructed.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram of a linear array ultrasonic probe according to an embodiment of the present invention,

[Fig. 2] A block diagram showing a schematic configuration of an electronic scanning ultrasonic inspection device using an example ultrasonic probe.

[Figure 3]
A diagram showing the installation state of the ultrasonic probe when testing a steel pipe using the same embodiment ultrasonic probe,

[Figure 4] Sensitivity characteristic diagram when testing the same steel pipe,

FIG. 5 is a schematic configuration diagram of a linear array ultrasonic probe according to another embodiment of the present invention,

[Fig. 6] A diagram showing the installation state of the ultrasonic probe when testing a steel plate using the same example ultrasonic probe,

[Figure 7
] Schematic diagram of a conventional linear array ultrasonic probe,

FIG. 8 is a schematic configuration diagram of another conventional linear array ultrasound probe.

[Explanation of symbols]

3...Object, 22,40...Linear array ultrasound probe,
23, 46... Back layer, 24, 45... Electrode plate, 25, 42
... Vibrator plate, 26, 43... Common electrode, 27, 44... Matching layer, 28... Electronic scanning ultrasonic inspection device, 29... Pulse generator, 30... Amplifier, 31... Detector, 32, 41... Unit detector Tentacle, 33...Scanning channel control section, 37...Steel pipe, 3
8...acoustic wedge, 48...steel plate.

Claims (4)

[Claims] Claim 1: A linear array ultrasonic probe in which a plurality of unit probes are arranged in a straight line, comprising one transducer plate made of a piezoelectric polymer material, and a transducer plate made of a piezoelectric polymer material. A plurality of electrode plates arranged linearly on the upper surface and corresponding to each of the unit probes, a back layer that commonly covers the upper surface of each of the electrode plates, and a single electrode plate attached to the lower surface of the transducer plate. A linear array ultrasonic probe comprising a common electrode plate and a matching layer attached to the lower surface of the common electrode plate. 2. A linear array ultrasonic probe in which a plurality of unit probes are arranged in a straight line, comprising one transducer plate made of a piezoelectric polymer material, and a transducer plate made of a piezoelectric polymer material. A plurality of electrode plates arranged linearly on the upper surface and corresponding to each of the unit probes, a back layer that commonly covers the upper surface of each of the electrode plates, and a single electrode plate attached to the lower surface of the transducer plate. a common electrode plate; a matching layer attached to the lower surface of the common electrode plate;
A linear array ultrasonic probe comprising an acoustic wedge formed of a polymeric material attached to the lower surface of the matching layer. 3. A linear array ultrasonic probe comprising a plurality of unit probes arranged in a plurality of rows, the transducer plate comprising one transducer plate made of a piezoelectric polymer material, and each of the rows. a plurality of electrode plates arranged linearly on the upper surface of the transducer plate in each row with a predetermined distance smaller than the unit probe spacing between each other, and corresponding to each of the unit probes; A linear array comprising: a back layer covering the upper surface of the plate; a common electrode plate attached to the lower surface of the vibrator plate; and a matching layer attached to the lower surface of the common electrode plate. Ultrasonic probe. 4. In a linear array ultrasonic probe in which a plurality of unit probes are arranged in a straight line, each unit probe includes a transducer plate made of a piezoelectric polymer material and a transducer plate made of a piezoelectric polymer material; a first electrode plate attached to the top surface of the vibrator plate;
a back layer attached to the upper surface of the electrode plate; a second electrode plate attached to the lower surface of the vibrator plate; and a matching layer attached to the lower surface of the second electrode plate. A linear array ultrasonic probe featuring: