JPH063456A - Ultrasonic inspection instrument - Google Patents

Abstract

PURPOSE:To provide an ultrasonic inspection instrument which is adapted to inspect the presence of a matter in a specimen automatically with higher reliability in a non-destructive manner. CONSTITUTION:A probe 11 for transmission and a probe 12 for reception are arranged facing each other on both sides of an inspection hole 6 of a belt 5 running on a conveyor 2. A specimen S is held with a holder 7 having the belt 5 and moved between the probes 11 and 12 for transmission and reception. An ultrasonic beam is radiated to the moving specimen S from the probe 11 for transmission. An ultrasonic beam transmitted through the specimen S is received with the probe 12 for reception. A judging device of the apparatus body 13 examines whether the amplitude of the received signal is below a fixed value or not to determine the acceptance or rejection of the speciment S.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic inspection apparatus for nondestructively inspecting the inside of a subject.

[0002]

2. Description of the Related Art FIG. 9 shows the structure of a conventional ultrasonic inspection apparatus. In FIG. 9, 91 is an ultrasonic probe, and 92
Is a transmitting unit, 93 is a receiving unit, 94 is a display unit, and S is a subject.

The above configuration will be described in more detail below along with its operation. Transmitter 92 to probe 91
When the pulse drive signal is sent to the probe 91, the probe 91 converts the pulse drive signal into ultrasonic waves, and the probe 91 emits an ultrasonic beam toward the subject S. Reflected or scattered waves are generated from the subject S according to the structure thereof, again reach the probe 91, are converted into electric signals, and are transmitted to the receiving unit 93 as reception signals. The received signal is amplified by the receiving unit 93,
Processing such as detection is performed, and the waveform is displayed on the display unit 94.

As described above, also in the above-described conventional ultrasonic inspection apparatus, non-destructive inspection is performed for defects and scratches inside the subject S, and the presence or absence of objects, from the waveform, amplitude, arrival time, etc. of the received signal. be able to.

[0005]

However, in the above-described conventional ultrasonic inspection apparatus, the ultrasonic probe 91 is manually operated to irradiate the subject S with ultrasonic waves. Therefore, the irradiation position cannot be determined with good reproducibility, the received signal fluctuates greatly, and an error may occur in the inspection, and there is a problem that the inspection work efficiency is poor.

The present invention solves such a conventional problem. By using the transmission method, it is possible to improve the accuracy of determination of the quality of the object and to continuously and automatically inspect the object. It is an object of the present invention to provide an ultrasonic inspection apparatus capable of improving the inspection work efficiency.

[0007]

In order to achieve the above object, the present invention provides a moving device for continuously moving a subject,
A transmitting probe for transmitting and scanning an ultrasonic beam to a subject moving by this moving device, a receiving probe for receiving and scanning an ultrasonic beam transmitted from the transmitting probe and transmitted through the subject, and a receiving probe It is provided with means for determining whether the object is good or bad by detecting whether or not the amplitude of the signal received by the probe is below a certain value.

[0008]

According to the present invention, therefore, the subject is continuously moved by the moving device, while the subject is scanned with the ultrasonic beam by the transmitting probe and the ultrasonic beam transmitted through the subject is transmitted. The subject can be continuously and automatically inspected by receiving the signal with a receiving probe that scans in synchronization with the trust probe and detecting a change in the amplitude of the received signal by the determination unit.

[0009]

【Example】

(Embodiment 1) Hereinafter, a first embodiment of the present invention will be described with reference to the drawings.

FIGS. 1A and 1B are a schematic plan view and a partially cutaway schematic side view showing an ultrasonic inspection apparatus according to a first embodiment of the present invention, respectively.

As shown in FIGS. 1 (a) and 1 (b), a water tank 1
A conveyor 2 is provided as a device for continuously moving the subject S therein. In the conveyor 2, a belt 5 is hung on belt wheels 3 and 4, and one belt wheel 3 is intermittently rotated by an intermittent drive source (not shown) such as a stepping motor, so that the belt 5 is intermittently moved in the direction of arrow x. Be driven. Holes 6 for inspection are formed in the belt 5 at regular intervals, and a pair of holders 7 are attached to the outer surface of the belt 5 in the front and rear of the running direction of the holes 6 for inspection to hold each group. The tool 7 can detachably hold the subject S on the inspection hole 6. The conveyor 2 is immersed in the water 8 filled in the water tank 1. A supply device 9 for holding the outer edge of the subject S on a holder 7 on the belt 5 is provided on the upstream side of the transfer side of the conveyor 2, and the subject S is held on the downstream side of the holder 7.
Sorting device 10 that takes out from the product and sorts it into good products and defective products
Is provided. A linear scanning type transmission probe 11 and a reception probe 12 that control transmission scanning and reception scanning of the ultrasonic beam are provided at an intermediate portion on the transfer side of the conveyor 2 so as to face the inspection hole 6. The device main body 13 includes a transmitter for transmitting a transmission signal to the transmitter probe 11, a receiver for performing processing such as amplification of a reception signal transmitted from the reception probe 12, and a good or defective of the subject S from the reception signal. It has a determination unit for performing the determination, and a controller for controlling the supply device 9, the sorting device 10, the conveyor 2, and the like.

The operation of the above configuration will be described below. The subject S is held by the holder 7 of the conveyor 2 which is not driven by the supply device 9 and immersed in the water 8.
After the supply of the subject S, the conveyor 2 is driven by intermittent driving to cause the belt 5 to intermittently travel in the direction of the arrow x at a constant speed, and the subject S held by the holder 7 of the belt 5 accordingly. To move. When the subject S enters the measurement range,
A transmission signal is sent from the transmission unit of the apparatus body 13 to the transmission probe 11, and measurement is started. The transmission probe 11 is a linear array type, and scans the subject S by sequentially sending an ultrasonic beam in the direction of arrow y.

2A to 2C are explanatory views of the ultrasonic beam scanning state, FIG. 2A is a view seen from the traveling direction of the conveyor, and FIG. 2B is a scanning of the ultrasonic beam. FIG. 2C is a view seen from the direction, and FIG. 2C is a view showing the trajectory of scanning of the ultrasonic beam on the subject as seen from above. The ultrasonic beam emitted from the transmission probe 11 and transmitted through the subject S is received by the reception probe 12, converted into a reception signal, and sent to the reception unit of the apparatus body 13. The receiving probe 12 is of the same linear array type as the transmitting probe 11 and is arranged at a position opposed to the subject S via the subject S, and is linearly scanned so as to receive the received signal in synchronization with the transmitted signal (see FIG. Two
(C) S1 to SN) is performed.

In the following, as a specific example, in pearl culture,
The case of non-destructively inspecting the presence or absence of pearls in the mother shellfish during aquaculture will be described.

FIG. 3 (a) is a plan view showing a mother oyster as an object, FIG. 3 (b) is a sectional view showing the mother pearl oyster, and FIG. 3 (c) is a holder 7 on the conveyor for holding the mother pearl oyster. It is a partial fracture | rupture side view which shows the made state. The mother shellfish which is the subject S has a thickness of 1-2 mm
A pearl S3 having a diameter of 5 to 8 mm, which is composed of a piece of shells S1 and S2, is embedded in the organ. When the mother shellfish S is irradiated with an ultrasonic beam from the transmitting probe 11, the incident beam is attenuated by reflection or absorption depending on the structure of the mother shellfish S and reaches the receiving probe 12 in the process of passing through the mother shellfish S. To do.

FIG. 4 is a diagram showing the relationship between the transmitted sound wave and the received sound wave. The received sound wave reaches the receiving probe 12 after a certain propagation time after being transmitted, and its amplitude becomes smaller than the amplitude of the incident sound wave. . 5A and 5B show distributions of amplitudes of received sound waves when the ultrasonic beam is scanned so as to pass through the mother shellfish S. Since the thicknesses of the shells S1 and S2 of the mother shellfish S are substantially uniform, the ultrasonic beam irradiation location A,
The fluctuation of the sound wave absorption by B is small, and since it is flat, the change of the reflection is also small. Further, since the absorption by the built-in is smaller than that of the shells S1 and S2, it can be ignored. Therefore, the attenuation of the sound wave by the mother shellfish S can be regarded as substantially constant in each part, and the amplitude V1 of the received sound wave at that time is substantially constant. When the mother shellfish S contains pearls S3, when an ultrasonic beam having a width smaller than the diameter of the pearls S3 passes through the pearls S3 as shown by B, it is attenuated by reflection and absorption at the pearls S3, and the received sound waves The amplitude is V2, which is smaller than V1. As an example, 3.5MHz
When the sound wave of the frequency of is transmitted through the pearl S3, the attenuation is about 40 dB. Therefore, by adding a discriminator to the receiving section of the apparatus body 13, the pearl S in the mother shellfish S is utilized by utilizing the large difference in the amplitude of the received sound wave depending on the presence or absence of the pearl S3.
The presence or absence of 3 can be determined.

FIG. 6 is a schematic block diagram of the judging device, and FIG. 7 is a timing chart for explaining the operation of the judging device. 6,
As shown in FIG. 7, the determiner causes the transmission signal trigger 61 to generate a gate signal from the gate signal generator 62, and the gate signal 63 causes the gate 64 to open at the reception time.
The received signal 65 is input to the gate 64, selected, and the input 66 is guided to the comparator 67. The comparator 67 is configured to output an output 68 according to the received signal when the received signal has a predetermined amplitude V or less. Therefore, the presence / absence of the pearl S3 can be determined by this determiner, and accordingly, the delivery device 10 (see FIG. 1).
Thus, the subject S for which the determination has been completed can be taken out from the stopped conveyor 2 and separated. Hereinafter, by repeating the above operation, the presence or absence of the pearl S3 in the mother oyster S can be continuously and automatically inspected and classified.

(Second Embodiment) A second embodiment of the present invention will be described below with reference to the drawings.

FIG. 8 shows an ultrasonic inspection apparatus according to the second embodiment of the present invention, as seen from the traveling direction of the conveyor.

In this embodiment, as shown in FIG.
A single element probe is used as the transmission probe 81 and the reception probe 82, and is configured to mechanically scan in the arrow y direction by the drive units 83 and 84. Other configurations are the same as those of the first embodiment. It is similar to the embodiment.

In the second embodiment shown in FIG. 8, a single element probe is used for both transmission and reception, but one of the transmission and reception is a linear scanning type probe as in the first embodiment. The ultrasonic beam may be used for electronic scanning, while the single element probe may be used for mechanical scanning. In addition to the above, the present invention can be modified in various ways without departing from the basic technical idea thereof.

[0022]

As described above, according to the present invention, the presence or absence of an object in a subject is determined by using the transmission method.
As compared with the reflection method of the above-mentioned conventional example, highly accurate determination can be performed. Further, since the ultrasonic beam is scanned on the subject that is continuously moving to perform the inspection and the determination of the inspection is made based on the amplitude of the received signal, the automatic inspection can be performed quickly.

[Brief description of drawings]

FIG. 1A is a schematic plan view showing an ultrasonic inspection apparatus according to a first embodiment of the present invention, and FIG. 1B is a partially cutaway schematic side view showing the ultrasonic inspection apparatus.

FIG. 2A is an explanatory view showing a scanning state of an ultrasonic beam by the ultrasonic inspection apparatus from a traveling direction of a conveyor. FIG. 2B is a diagram showing a scanning state of an ultrasonic beam by the ultrasonic inspection apparatus from a scanning direction. Explanatory drawing (c) is a plan view showing a scanning trajectory of an ultrasonic beam on a subject by the ultrasonic inspection apparatus.

FIG. 3A is a plan view showing a mother pearl oyster as an example of a subject, FIG. 3B is a cross-sectional view showing the mother pearl oyster, and FIG. Partially cutaway side view

FIG. 4 is an explanatory diagram showing a relationship between a radiated sound wave and a received signal by the ultrasonic inspection apparatus according to the embodiment of the present invention.

5A is a diagram showing an ultrasonic beam irradiation position on a subject by the ultrasonic inspection apparatus according to the embodiment of the present invention. FIG. 5B is a diagram showing the ultrasonic beam irradiation position shown in FIG. Explanatory diagram showing distribution

FIG. 6 is a schematic block diagram showing a judging device used in the ultrasonic inspection apparatus according to the embodiment of the present invention.

FIG. 7 is a timing chart for explaining the operation of the determiner.

FIG. 8 is a schematic explanatory view showing an ultrasonic inspection apparatus according to a second embodiment of the present invention, as seen from the traveling direction of the conveyor.

FIG. 9 is a schematic block diagram showing a conventional ultrasonic inspection apparatus.

[Explanation of symbols]

 1 Water Tank 2 Conveyor 7 Holding Device 9 Supply Device 10 Sorting Device 11 Transmitting Probe 12 Receiving Probe 13 Device Main Body S Specimen

Claims (1)

[Claims] 1. A moving device for continuously moving a subject,
A transmitting probe for transmitting and scanning an ultrasonic beam to a subject moving by this moving device, a receiving probe for receiving and scanning an ultrasonic beam transmitted from the transmitting probe and transmitted through the subject, and a receiving probe An ultrasonic inspection apparatus comprising: means for determining whether a test object is good or bad by detecting whether or not the amplitude of a signal received by a probe is below a certain value.