JPS6110205Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to an ultrasonic flaw detector that is convenient for collecting recorded results as evidence when performing non-destructive testing using an ultrasonic flaw detector.

Ultrasonic flaw detection in nondestructive testing is very useful, but since the test results are images on a cathode ray tube, pattern recognition requires skill.
In order to eliminate individual errors in visual inspection, and because the test materials are often expensive and important parts such as aircraft parts and generator parts, which can lead to serious accidents if a defect occurs, the inspection results are used as evidence for quality assurance. It is necessary to keep it as a record. Furthermore, there may also be cases where records are required to be analyzed as materials for judgment by both parties involved in the transaction. In response to these demands, photography has conventionally been carried out, but recently, recording has begun to be carried out using a combination of an A-scope recorder and a pen recorder. An example of flaw detection using this invention will be explained with reference to FIG. In FIG. 1, the tester holds the probe 4 on the test material 5 via the couplant 8 with his/her hand while operating the operating devices on the panels of the ultrasonic flaw detector 1 and the A-scope recorder 2 with another hand. The inspection proceeds by operating and monitoring the image shown on the surface of the cathode ray tube 3 of the ultrasonic flaw detector 1, and when the reflected image from the defect 10 appears between the reflected images from the front and back surfaces of the test material 5. In conventional flaw detection, the pen recorder 6 is driven by the operating device on the panel surface of the A-scope recorder 2, and a record is taken on the recording paper 7. In this case, it takes about 10 seconds for the pen recorder to complete recording, so the tester must make efforts to keep the image steady during this time. The contact method for holding the probe 4 is delicate and requires careful attention.
In order to confirm the state and position of the A-scope recorded waveform on the pen recorder, it was necessary to look beyond the surface of the cathode ray tube 3. According to this invention, it is only necessary to gaze within one field of view on the surface of the cathode ray tube 3, which reduces the physical and mental burden on the examiner.

This idea is based on the fact that when a nondestructive tester records an A-scope flaw detection waveform, a bright spot 9 shown in Figure 1 moves sequentially on the flaw detection waveform on the cathode ray tube surface for about 10 seconds to complete the recording. This has the effect of clearly showing where the pen recorder is currently writing, allowing the tester to concentrate his/her attention, stably fixing the probe 4 and the test material 5, and completing a good record. The purpose is to provide ultrasonic flaw detectors.

One embodiment of this invention is shown below in Figure 2, which is a block circuit diagram centered on the A-scope recorder.
This will be explained with reference to FIG. 3, which is a time chart of signal waveforms at the points indicated by lowercase letters in the figure. In FIG. 2, the time control circuit 11 sends a synchronizing signal a to a transmitting/receiving circuit 12, a swept sawtooth wave signal C to a sampling pulse width generating circuit 14, and an unblanking signal h to a mixer circuit 18. Control timing. The transmitter/receiver circuit 12 sends a transmission pulse to the probe 4 in synchronization with the synchronization signal a, and a portion of the ultrasonic pulse converted by the probe 4 is reflected from the surface of the test material 5 via the couplant 8. However, the other part is the defect 10, and the remaining part is reflected from the back surface of the test material 5 and enters the probe 4, where it is converted into an electric signal again and becomes the received signal e, which is sent to the sampling circuit 15 via the transmitting/receiving circuit 12. Enter.
The sampling pulse width generation circuit 14 receives the sweep sawtooth wave signal C and the recording sawtooth wave signal b generated by the recording time generation circuit 13, and generates a pulse at the coincident time of both signals, and at the same time generates a pulse with a predetermined pulse width. It consists of a blocking oscillator with
A sampling signal d having a pulse width of several 100 ns is sent to the sampling circuit 15 and the mixer circuit 18. A sampling circuit 15 samples the received video signal e using a sampling signal d, and outputs a sampling output signal f to a peak hold circuit 16.
send to The peak hold circuit 16 sends the peak hold output signal g to the pen recorder circuit 17. The sampling pulse width generating circuit 14, the recording time generating circuit 13, the sampling circuit 15, and the peak hold circuit 16 constitute the A scope recorder 2 shown in FIG. The pen recorder circuit 17 belongs to the pen recorder 6 shown in FIG. 1, and drives the pen using the peak hold output signal g to write a record on the recording paper. The mixer circuit 18 is a circuit added according to this invention, and generates a brightness-modulated unblanking signal i by superimposing the unblanking signal h and the sampling signal d, which increase the brightness only when there is an input signal to the cathode ray tube. Send to circuit 19. Since the signal i moves on the unblanking signal h in synchronization with the sampling signal d, a bright spot brighter than the swept bright line synchronizes with the pen whose movement timing is given in accordance with the movement of the sampling signal d. Move on the image on the cathode ray tube.
Therefore, by observing the bright spot, it is possible to know the movement of the pen recorder from the start to the end of recording. The time control circuit 11, the transmitting/receiving circuit 12, the mixer circuit 18, and the cathode ray tube circuit 19 belong to the ultrasonic flaw detector 1 shown in FIG. In Fig. 3, for example, the repetition frequency of the synchronizing signal a is 1 KHz, that is, the number of sweeps of the sweeping sawtooth wave signal c is 1000 times per second, and the time and interval of the recording sawtooth wave signal b, that is, the time it takes for the pen to draw one image. If is 10 seconds, the number of sweeps in 10 seconds is
10,000 times, and the interval at which the sampling signal d moves is an interval obtained by dividing one sawtooth wave signal of the swept sawtooth wave signal c into 10,000 equal parts, and the sampling effect is sufficient.

As explained above, this invention allows non-destructive testers to maintain a stable A-scope waveform by simply gazing at the bright spot when recording the A-scope flaw detection waveform as a valuable inspection record, making it possible to complete good records. It is possible to provide an ultrasonic flaw detector with great practical effects.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram showing flaw detection being carried out by the ultrasonic flaw detector according to this invention, Fig. 2 is a block circuit diagram showing one embodiment of this invention, and Fig. 3 is the main points shown in Fig. 2. This is a time chart of the signal waveform. 1... Ultrasonic flaw detector, 2... A scope recorder, 3... Braun tube, 4... Probe, 5... Test material, 6... Pen recorder, 7... Recording paper, 8...
...Coupler, 9...Bright spot, 10...Defect, 11...
...Time control circuit, 12... Transmission/reception circuit, 13...
Recording time generation circuit, 14...Sampling pulse width generation circuit, 15...Sampling circuit, 16...
... Peak hold circuit, 17 ... Pen recorder circuit, 18 ... Mixer circuit, 19 ... Braun tube circuit, a ... Synchronization signal, b ... Recording sawtooth wave signal, c ... Sweeping sawtooth wave signal, d ... ...sampling signal, e...received video signal, f...sampling output signal, g...peak hold output signal,
h...Unblanking signal, i...Brightness modulation unblanking signal.

Claims (1)

[Scope of utility model registration request] In an ultrasonic flaw detector that records the A scope flaw detection waveform displayed on the cathode ray tube surface with a pen recorder, the bright spot synchronized with the pen recorder is
An ultrasonic flaw detector characterized in that the position recorded by the pen recorder is displayed superimposed on a scope flaw detection waveform.