JPS582743A - Ultrasonic probe - Google Patents

Abstract

PURPOSE:To generate and detect longitudinal waves and transversal waves selectively with one probe, by providing two coils for magnet and changing the direction of a generated magnetic field by the selection of them. CONSTITUTION:The first coil 11 for magnet is wound around a column 10a of an iron core 10 for magnet, and the second coil 12 for magnet is wound around a cylinder 10b of the iron core 10. The first flat coil 13 is arranged near the lower end of a groove 10c between the column 10a and the cylinder 10b of the iron core 10, and the second flat coil 14 is arranged in the lower end face of the column 10a. When the coil 11 is selected, the spiral first flat coil 13 is used as a coil for generating and detecting an eddy current to obtain the probe for generating and detecting ultrasonic waves of logitudinal waves. When the coil 12 is selected, the seocnd flat coil 14 is used to obtain the probe for generating and detecting ultrasonic waves of transversal waves.

Description

[Detailed description of the invention] This invention generates ultrasonic waves in metal without contact.

This invention relates to an ultrasonic probe for detecting electromagnetic ultrasonic waves.

2. Description of the Related Art Conventionally, as electromagnetic ultrasonic probes, those shown in FIGS. 1 and 2 are known. Of these, Figure 1 is a sectional view of a probe that generates and detects longitudinal ultrasound waves, and Figure 2 is a sectional view of a probe that generates and detects transverse ultrasound waves. In both Figures 1 and 2, l is the material to be tested that has a conductive surface, 2.5 mm is the magnet core made of ferromagnetic material, and 3.6 is the core 2.5 mm. The wound magnet coils 4 and 7 are flat spiral coils disposed at the ends of the magnet core 2.7, respectively.

Magnet coil 3 has drawers 1, 31 and 32, and magnet coil 6 has drawer l! I6
1.62 is provided. Further, the flat spiral coil 4 is provided with drawers @41 and 42. Similarly, the flat spiral coil 7 is also wound with lead wires 71 and 72. 'Next, the operation of the electromagnetic ultrasonic probe shown in FIGS. 1 and 2 will be explained. First, in the case of Figure 1.

A probe that generates longitudinal ultrasound waves in the specimen 1 or detects longitudinal ultrasound waves in the material 1 to be examined.
2, when a current is passed through the magnet coil 3, the iron core 2
A magnetic field is generated at the end.

When this is placed opposite to the material to be inspected, the surface of the material to be inspected is 1.
A magnetic field parallel to the surface can be applied.

When an oscillating current as shown in Fig. 3 is passed through the flat spiral coil 4 provided at the end of the iron core 2 through the leads 41 and 42, an eddy current is generated on the surface of the test material l.゛C occurs. The interaction (Lorentz force) between this eddy current C and the magnetic field generates a force like E.

If the magnetic field A is constant, this field E changes in the same way as the eddy current C, and a longitudinal ultrasonic wave is generated in the specimen l.

Detection of longitudinal ultrasonic waves in the specimen l is performed on the completely opposite principle to the generation described above. That is, when the ultrasonic wave reaches near the surface of the material to be inspected 1 and vibrates as shown in E.

Since there is a magnetic field there, eddy currents are generated near the surface. Since this induces a voltage in the flat spiral coil 4, this can be detected by the extractors [41, 42].

On the other hand, in the case of Fig. 2, a probe that generates transverse ultrasonic waves in the test material l or detects transverse ultrasonic waves in the test material l,
When a current is passed through the magnet coil 6 from the lead wires 61 and 62, a magnetic field B is generated at the end of the iron core 5. When this is placed opposite the material 1 to be tested, a magnetic field can be applied to the surface of the material 10 to be tested in a direction perpendicular to the surface.

At this time, in the flat spiral coil 7 provided at the end of the iron core 5,
When an oscillating current as shown in FIG. 3 is passed through the lead wires 71 and 72, an eddy current is generated on the surface of the test material l. Due to the interaction between this eddy current and the magnetic field B, 4
7. A force like F is generated. If the magnetic field B is constant,
This side P changes in the same way as the eddy current, and a transverse ultrasonic wave is generated in the specimen l. Also detection of transverse ultrasound waves. This occurs based on the exact opposite principle to the above generation.

Generally, in electromagnetic ultrasonic generation and detection.

Ultrasonic waves of various modes can be generated or detected depending on the direction of the magnetic field applied to the surface of the material to be tested and the winding of the coil provided at the end of the iron core.

In conventional electromagnetic ultrasonic probes, the direction of the magnetic field applied to the surface of the test material differs depending on whether the ultrasonic wave generated is a single wave or a transverse wave, so separate iron cores are required for each type. Each requires a dedicated probe, and when inspection using longitudinal waves and transverse waves is required, two probes are required, and there are disadvantages such as the need to replace them frequently. .

This invention was made in order to eliminate the above-mentioned drawbacks of the conventional technology.A second magnet coil is provided on the outside of an iron core similar to the iron core for generating and detecting longitudinal ultrasonic waves, and this second magnet Depending on the selection of the coil, it is necessary to generate a magnetic field that is horizontal or perpendicular to the surface of the material being tested.
The object of the present invention is to provide an electromagnetic ultrasonic probe that can generate and detect longitudinal or transverse ultrasonic waves.

Hereinafter, one embodiment of the ultrasonic probe of the present invention will be described with reference to the drawings. FIG. 4 is a cross-sectional view showing one embodiment thereof,
In FIG. 4, 101j is a magnet core made of ferromagnetic material, 11 is a first magnet coil, and 12 is a magnet core made of a ferromagnetic material.
a Second magnet coil.

The magnet core IO consists of a cylinder 10a and a cylinder 10b surrounding it, and includes a first magnet coil 1.
The second magnet coil 12 is wound so as to include the cylinder 10b of the magnet core IO, that is, the entire magnet core IO. has been done. therefore.

The first magnet coil 11 and the second magnet coil 12 are arranged concentrically.

A first flat coil 13 is arranged near the lower end of the groove 10C between the cylinder 101 and the cylinder 10b of the magnet core IO, and a second flat coil 14 is arranged on the lower end surface of the cylinder 10m.

The first magnet coil 1.1 has a lead wire 11L.
is led out, and a lead wire 12L is also led out to the second magnet coil.

Output lines 13L and 14L are also led out from the first flat coil 13 and the second flat coil 14, respectively.

Next, the operation of the ultrasonic probe of the present invention configured as described above will be described using the operation explanatory diagrams of FIGS. 5 and 6. In Figure #E4, if the first and second magnet coils 11 and 12 are selectively used, a magnetic field as shown in Figures 5 and 6 will be generated at the end of the magnet core 1o. I can do it.

FIG. 5 shows the case where the first magnet coil 11 is selected, and by using the spiral first flat coil 13 as a coil for generating and expanding eddy current,
This is the same as the conventional probe 10 shown in FIG. 1, which generates and detects longitudinal ultrasonic waves.

In addition, Fig. 6 shows the case where *2 magnet coil 12 is selected, and the case where the second flat coil 14 is used as the coil for generating or detecting eddy current is shown in Fig. 2. This is the same as the conventional probe shown above that generates and detects transverse ultrasonic waves.

In the above embodiment, the second flat coil 14 is provided on the end face of the cylinder 10a of the magnet core 10, but it may also be provided on the end face of the cylinder 10b. It may be provided over both the cylinder 10b and the cylinder 10b.

Furthermore, the column part and the cylindrical part of the magnet core 10 are cylindrical,
Although cylinders have been described, these may also be prismatic or rectangular cylinders.

As described above, according to the ultrasonic probe of the present invention, two magnet coils are provided and the direction of the generated magnetic field can be changed by selecting one of them, so that only one probe can be used. , it has the advantage of being able to selectively generate and detect longitudinal and transverse ultrasound waves.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of a conventional ultrasonic probe that generates and detects longitudinal ultrasonic waves, and Fig. 2 is a cross-sectional view of a conventional ultrasonic probe that generates and detects transverse ultrasonic waves. 3 is a diagram showing the waveform of the current flowing through the rounded flat coil that generates ultrasonic waves in the ultrasonic probe shown in FIG. 1 and FIG. 2, and FIG. 5 and 6 are diagrams showing the operation of the ultrasonic probe of the present invention, respectively. 10---rlP4":) Iron core for 10a-Cylinder, Job...Cylinder, 10cm...Groove, 11...1st
Iron core for magnet k, l: j:...Second! Coil for magnet z, 13...first flat coil m14...
Second flat coil, ltL~14 L-... Leading wire. 2t? , In the figure, the same part is indicated by the same name. Agent Shin Kuzuno −

Claims (1)

[Claims] a magnet core made of nine ferromagnetic material having a columnar part and a cylindrical part with a groove formed therebetween; a first core wound around the columnar part;
a second magnet coil wound around the cylindrical portion and centripetal to the first magnet coil; a second magnet coil disposed at a predetermined location on the lower end surface of the magnet core; A first flat coil that generates and detects KJl-wave ultrasonic waves when the coil is selectively excited; An ultrasonic probe comprising a second flat coil that generates and detects ultrasonic waves.