JPH06288996A - Ultrasonic probe - Google Patents

Abstract

PURPOSE:To provide an ultrasonic probe which can effectively cope with objects to be inspected having different external surface shapes. CONSTITUTION:The title probe is provided with an ultrasonic vibrator 1 and waveguide body 2 which propagates ultrasonic waves outputted from the vibrator 1 to a pipe which is an object to be inspected. The vibrator 1 uses a concave piezoelectric element 3 having a concave output surface. The focal point of the piezoelectric element 3 is set at the front end section of the waveguide body 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to an ultrasonic probe,
Particularly, it relates to an ultrasonic probe provided with a waveguide.

[0002]

2. Description of the Related Art Conventionally, for a subject having a complicated surface shape, it has been attempted to propagate an ultrasonic wave into the subject by using a waveguide.

FIG. 6 shows an example thereof. In the conventional example shown in FIG. 6, when an ultrasonic wave for searching for a foreign object having a predetermined frequency is sent into the tube 50 as an object or a reflected wave from the tube 50 is received, the outer diameter of the tube 50 is changed. In addition, the cylindrical cutout 51A, which is somewhat larger than the tube, is attached to the waveguide 5
1 is formed on the contact surface on the side of the pipe 50, and the cylindrical cutting portion 51
A method of bringing A into contact with the pipe 50 is adopted. This kind of abutting work on the pipe 50 is actually performed through an oil layer such as machine oil in order to eliminate the inclusion of bubbles. Further, in this conventional example, the ultrasonic transducer 49 having a flat output surface is used.

FIG. 7 shows another conventional example. In the conventional example shown in FIG. 7, an ultrasonic transducer 59 having a convex shape on the output side is used in order to propagate an ultrasonic wave for foreign matter search through the waveguide 61 to the entire inside of the tube 50.

[0005]

However, in the conventional example shown in FIG. 6, when ultrasonic waves are propagated through the waveguide 51 into the tube 50 which is the subject, as shown in FIG. In addition, there is a disadvantage that the ultrasonic waves are converged in the tube 50 due to the catadioptric action on the boundary surface and the ultrasonic waves cannot be uniformly propagated to the entire inside of the tube 50.

On the other hand, in the conventional example shown in FIG.
The property of the ultrasonic transducer 55 having a convex shape on the output side, that is, the diffusive propagation action of the ultrasonic wave and the catadioptric action at the boundary surface sequentially function, and as shown in FIG. There is an advantage that it can be propagated almost uniformly.

However, in the conventional example shown in FIGS. 6 to 7, in order to deal with all the tubes 50 having different diameters, a plurality of ultrasonic probes provided with corresponding waveguides 51 and 61. There has been an inconvenience that the tentacles must be prepared in advance.

[0008]

It is an object of the present invention to improve the disadvantages of the conventional example, and one ultrasonic probe can effectively cope with a subject having a different outer surface shape. The purpose is to provide an ultrasonic probe.

[0009]

According to the present invention, there is provided an ultrasonic probe including an ultrasonic transducer and a waveguide for propagating ultrasonic waves output from the ultrasonic transducer to a subject,
As the ultrasonic transducer, a concave piezoelectric element whose output surface is concave is used, and the focal point of the concave piezoelectric element is set at the tip of the waveguide. In this way, the above-mentioned purpose is achieved and used.

[0010]

[Operation] First, when the ultrasonic probe is attached to a predetermined position on the outer surface of the subject and set to the operating state, the ultrasonic waves output from the ultrasonic transducer are transmitted inside the waveguide to the subject contact surface. Converge and propagate toward. The ultrasonic waves that have converged on the subject contact surface pass through the focal point and then radiatively propagate toward the inside of the tube. Therefore, the ultrasonic waves propagated inside the pipe can cover the inside of the pipe over a wide range. If the radius of curvature of the concave piezoelectric element is set to be large, the spread of this ultrasonic wave can be further expanded in the tube.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. The embodiment shown in FIGS. 1 to 5 includes an ultrasonic transducer 1 and a waveguide 2 for propagating the ultrasonic wave output from the ultrasonic transducer 1 to a tube 50 as a subject. . In this embodiment, a concave piezoelectric element 3 having a concave output surface is used as the material of the ultrasonic vibrator. Reference numeral 2A indicates a convex piezoelectric element mounting surface 2 formed on one end surface of the waveguide 2. Further, the focal point P of the concave piezoelectric element 3 is set to the center of the tip end surface of the waveguide body 2 described above, that is, the object contact surface 2B in this embodiment.

As the waveguide body 2, a waveguide body having a generally cylindrical shape and a tip end portion formed in an inverted conical shape is used. The waveguide 2 is selected and used so that its acoustic impedance value is close to that of the concave piezoelectric element 3 and its attenuation constant is low.

In the waveguide 2, the piezoelectric element mounting surface 2A on which the concave piezoelectric element 3 is mounted is a convex surface having a size matching the concave shape of the concave piezoelectric element 3. Further, the subject contact surface 2B of the waveguide 2 which contacts the above-mentioned tube 50 is a flat surface having a diameter of, for example, about 5 mm. Therefore, as shown in FIG. 4, ultrasonic waves can be effectively diffused and propagated inside the tube 50.

Further, since the focal point of the concave piezoelectric element 3 is set at the center of the object contact surface 2B of the waveguide 2 as described above, the waveguide 2 is surrounded by the side surface thereof.
Piezoelectric element mounting surface 2A without disturbing the propagation of ultrasonic waves
It is possible to form the taper gradually from the (or intermediate portion) toward the subject contact surface 2B.

In this case, the side surface of the waveguide 2 may be formed with a rotating body having an exponential curve, for example, so that the tip portion becomes thin. By doing so, it is possible to further reduce the reflection from the periphery of the side surface of the waveguide 2.

Next, the operation of the above embodiment will be described with reference to FIGS.
It will be described based on. First, as shown in FIG. 2, an ultrasonic probe is attached to a predetermined position on the outer surface of the tube 50, and the ultrasonic transducer 1
Is set to the operating state, the ultrasonic wave output from the ultrasonic transducer 1 converges and propagates inside the waveguide 2 toward the subject contact surface 2B. The ultrasonic waves converged on the subject contact surface 2B are gradually diffused while propagating in the tube 50. Such a situation is shown in FIG. Therefore, the ultrasonic waves propagated in the pipe 50 can cover the inside of the pipe 50 over a wide range. The spread angle α of this ultrasonic wave is determined by the concave piezoelectric element 3
If the radius of curvature is set to a large value, a larger divergence angle can be obtained in the tube 50.

As described above, in this embodiment, since the area of the object contact surface 2B, which is the tip end surface of the waveguide 2, is set to be extremely small, a plurality of tubes 50 as the object having different diameters are provided. One kind of ultrasonic probe can sufficiently and effectively cope with various kinds of objects, and the object is another object 60 having a complicated shape as shown in FIG. 5, for example. However, there is an advantage that this can be effectively dealt with.

Although the focal point P of the concave piezoelectric element 3 is set at the center of the object contact surface 2B of the waveguide 2 in the above embodiment, the present invention is not limited to this. Instead, for example, the focal point P of the concave piezoelectric element 3 may be set outside the subject contact surface 2B of the waveguide 2 or inside the subject contact surface 2B.

[0019]

Since the present invention is constructed and functions as described above, according to this, a concave piezoelectric element having a concave output surface is used as a material of an ultrasonic vibrator, and the concave piezoelectric element is used. Since the focal point of the element is set at the tip of the waveguide, it is possible to gradually taper the side surface of the waveguide toward the tip without disturbing the propagation of ultrasonic waves. , Therefore, it is possible to set the area of the tip end surface of the waveguide to a significantly small value. Therefore, one ultrasonic probe can be used for multiple types of tubes with different diameters. (EN) Provided is an excellent ultrasonic probe, which can be effectively dealt with sufficiently, and can be effectively dealt with even if the subject has a complicated shape. be able to.

[Brief description of drawings]

FIG. 1 is a partially omitted sectional view showing an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing the operation of FIG.

FIG. 3 is an enlarged explanatory view showing a contact state between the tip end surface of the waveguide and the subject in FIG.

FIG. 4 is an explanatory view showing the operation of FIG. 1, and is an explanatory view showing a situation of diffusion and propagation in the pipe.

FIG. 5 is an explanatory diagram showing a state of diffusion and propagation of ultrasonic waves propagating in another subject.

FIG. 6 is an explanatory diagram showing a conventional example.

FIG. 7 is an explanatory diagram showing another conventional example.

[Explanation of symbols]

 1 Ultrasonic transducer 2 Waveguide 2A Piezoelectric element mounting surface 2A 2B Subject contact surface 3 Recessed piezoelectric element 50 Tube as subject

Claims (4)

[Claims] 1. An ultrasonic probe provided with an ultrasonic transducer and a waveguide for propagating ultrasonic waves output from the ultrasonic transducer to a subject, wherein the material of the ultrasonic transducer is: An ultrasonic probe characterized in that a concave piezoelectric element whose output surface is formed in a concave shape is used, and the focus of the concave piezoelectric element is set at the tip of the waveguide. 2. The ultrasonic probe according to claim 1, wherein the focal point of the concave piezoelectric element is set at the center of the tip surface of the waveguide. 3. The ultrasonic probe according to claim 1, wherein the focal point of the concave piezoelectric element is set outside the tip end surface of the waveguide. 4. The ultrasonic probe according to claim 1, wherein the focal point of the concave piezoelectric element is set inside the tip end surface of the waveguide.