JPS6321550A - Ultrasonic prober - Google Patents

Abstract

PURPOSE:To detect a defect in an object to be inspected of any shape with a stable operation, by a method wherein a magnetic fluid is used as contact medium and a magnet is provided in such a manner as to fill an ultrasonic probe with the magnetic fluid, maintain the fluid and prevent the outflow thereof. CONSTITUTION:An ultrasonic probe 1 transmits an ultrasonic wave from an ultrasonic vibrator and receives and amplifies the reflected wave from the defect of an object 20 to be inspected to discover a fine defect. The probe 1 has a magnet 2 at a contact part with the object 20 being inspected and a smoothing member 3 with a low friction coefficient is made to adhere to the bottom of the magnet 2. A magnetic fluid 10 is used between the object 20 being inspected and the probe 1 as contact medium to fill a space formed with the object 20 being inspected and the probe 1 and to maintain it by a magnetic force of the magnet 2. This eliminates the mixing with air thereby eliminating a problem such as erroneous detection.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to an ultrasonic probe device for detecting welding defects, cast iron defects, and the like.

(Prior art) Conventionally, as shown in Figs. 3 and 4, a couplant (water, oil, glycerin, etc.) is applied onto the subject in order to increase the adhesion between the ultrasonic probe and the subject. In the case of automatic flaw detection, local water immersion was used.

In addition, there were some methods in which a polymer membrane was used as a couplant, as shown in Japanese Patent Application Laid-Open No. 60-225544.

(Problems to be Solved by the Invention) These couplants contaminate the specimen, cause it to rust, and even cause the probe to deteriorate or be damaged due to water and oil. .

In other words, depending on the type of object to be inspected, flaw detection may be performed on curved surfaces, inner wall surfaces, or even surfaces with severe irregularities such as cast surfaces. It is difficult for the couplant to become uniform, and furthermore, the couplant flows out.
There were problems such as air getting mixed in.

Furthermore, even in those using a polymer membrane, there is a problem in that the probe does not slide smoothly due to the large contact resistance with the surface of the object to be examined.

(Means and effects for solving the problems) The present invention has been made in view of the above-mentioned circumstances, and has the following objectives: 9. To prevent the couplant from flowing out and to make the operation smooth. An object of the present invention is to provide an ultrasonic probe device that enables stable ultrasonic flaw detection.

That is, by using a magnetic fluid as a couplant and providing a magnet at the contact portion of the ultrasonic probe with the subject, the magnetic fluid is retained and prevented from flowing out.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings. 1st
The figure is a schematic diagram showing one embodiment of the ultrasonic probe device of the present invention.

1 in the figure is an ultrasonic probe, which detects minute defects by transmitting ultrasonic waves from an ultrasonic transducer and receiving and amplifying reflected waves from defects. The ultrasonic probe 1 is equipped with a magnet 2 at the contact portion with the subject 20, and a smooth surface member 3 having a low coefficient of friction, such as Teflon, is adhered to the lower part of the magnet 2.

In such an ultrasonic probe device, the space formed by the subject 20 and the ultrasonic probe 1 is filled and held by the magnetic force of the magnet 2 with a magnetic fluid 10 as a couplant.

FIG. 2 is a schematic diagram showing another embodiment of the ultrasonic probe device of the present invention.

That is, in the embodiment shown in FIG. 1, the member 3 with a low coefficient of friction is used for the contact portion with the subject 20, but in the embodiment shown in FIG. This figure shows an ultrasonic probe device equipped with a holding member 5 for use with a rotating member 4 such as a roller bearing.

In the embodiment shown in FIG. 2, filling and retaining the magnetic fluid 10 is the same as in FIG. 1.

Further, the ultrasonic probe 1 may be cylindrical or prismatic, and the magnet 2 and the holding member 5 are provided to suit the shape of the ultrasonic probe 1 as appropriate.

(Effects of the Invention) As described in detail below, the present invention uses a magnetic fluid as a couplant, fills the ultrasonic probe 1 with the magnetic fluid,
Since the magnet 2 is installed to hold and prevent leakage, stable operation and defect detection are possible no matter what shape the specimen is. Also, since there is no air intrusion during automatic probe, there is no possibility of false detection etc. This has the effect of eliminating various problems.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view of one embodiment of the ultrasonic probe device according to the present invention, Fig. 2 is a cross-sectional view of another embodiment of the ultrasonic probe device according to the present invention, and Fig. 3 is a reverse mold. FIG. 4 is a sectional view showing a coating method, a polymer method, and a local water immersion method as conventional ultrasonic probe devices.

Claims (1)

[Claims] An ultrasonic probe characterized in that a magnet is provided at the contact part between the ultrasonic probe and the subject, and a space formed between the ultrasonic probe and the subject is filled and held with a magnetic fluid. tentacle device.