JPS62130353A - Ultrasonic automatic test equipment - Google Patents

Abstract

PURPOSE:To prevent the title test equipment from malfunctioning when contacting a steel plate, and a probe, etc. from being broken by utilizing an acoustic coupling check function and outputting a plate separation command to a probe holding mechanism based on a certain judgement in case of the generation of a defect in coupling. CONSTITUTION:When the probe holding mechanism 1 almost comes out of the steel plate 2, the contacting medium interposed between the probe U and steel plate 2 has a break and an ultrasonic wave echo generated by the probe U does not arrive any more, so that an acoustic coupling defect state is entered. Consequently, a data processing circuit 8 processes a flaw detection result by receiving a signal from a transmitting receiving circuit 7 and outputs a processing result Fo. An acoustic coupling check circuit 9, on the other hand, receives the signal from the circuit 7 to judge the acoustic coupling state and generates a signal CN as a coupling check result and a logical judging circuit 10 receives the signal CN from the circuit 9 and outputs the judgement result based upon certain logic as a judgement signal DN. Then a probe holding mechanism driving circuit 11 receives a control signal Di for the mechanism 1 and interlocks the driving command on the basis of the signal DN to prevent the probe, etc. from being broken.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention is applicable to automatic ultrasonic flaw detection equipment for plate materials such as steel plates. More specifically, the present invention relates to an automatic ultrasonic flaw detection device equipped with means for preventing mechanical damage to a probe and a probe holding mechanism.

[Conventional technology] In ultrasonic automatic flaw detection equipment for thick steel plates, in order to bring the probe and probe holding mechanism into or out of contact with the conveyed thick steel plate at the optimum timing, it is necessary to adjust the approach of the steel plate. It is often controlled by a sensor that detects the distance traveled or a length measuring device that outputs pulses according to the distance traveled. Figure 3 shows the situation at the time of contact. In Figure 9, (1) is the probe holding mechanism that houses the probe, (2) is the transport roll (3).
), a thick steel plate (cross section shown), +
41 is an entry detector that detects the entry of the steel plate, and (5) is a sub-head device that outputs a clock according to the traveling distance of the steel plate.

In this figure, (a) shows the state in which the intrusion detector (4) detects the tip of the steel plate (2) that has entered, and (b)
(C) is a state in which the tip of the steel plate (2) has been conveyed to just below the probe holding mechanism (11), and (C) is a state in which the travel is stopped or stopped by the pulse count of the sub-head device (5) after the state shown in (a). The probe holding mechanism (1) is shown in contact with the tip of the moving steel plate (2).
C) shows a case where the contact plate operation is performed normally, but there is a malfunction of the approach detector (4) and the length measuring device f (51).

It is conceivable that the steel plate may come into contact with the steel plate deviating from its normal position due to slipping or the like.

Figure 4 shows the state in which the probe holding mechanism fll is in contact with the steel plate (2) before its tip reaches its normal position.

The symbols in the figure correspond to those in FIG. If the situation as shown in this figure occurs, an accident may occur in which the probe or probe holding mechanism (11) is damaged by the running force of the steel plate (2).Measures to prevent such troubles Duplicating sensors has been considered as a solution, but no significant effect can be expected.

On the other hand, even if the plates are in contact at the normal position, if the steel plate is transported in an angled state, one of the multiple probe holding mechanisms installed in the width direction of the plate may Items on the side edges may protrude from the edge of the plate as it travels, potentially causing mechanical damage. Figure 5 shows this situation. In Figure 9, (1) shows the probe holding mechanism group seen from the top, and shows an example in which five units a""'e are arranged. is probe holding mechanism +1)
(B) shows the state in which the steel plate is in contact with the tip of the steel plate, (B) shows the state in which the steel plate is being inspected for flaws while moving diagonally, and (3) shows the conveying roll. As can be easily understood from this figure, when the steel plate moves diagonally, the probe holding mechanism shown in a
There is a risk that those on the side edges will pop out from the edge of the steel plate and be damaged. In order to prevent such damage accidents, countermeasures are being considered, such as installing plate edge detection sensors on or near the contact surface with the steel plate of the probe holding mechanism to protect it from occurring. .

[Problem that the invention seeks to solve]

As mentioned above, in conventional equipment, attempts have been made to reduce the probability of malfunction by such methods as duplicating the board edge detection sensor, installing a separate dedicated sensor for protection, and checking the sensor operation in sequence. However, adding new sensors poses placement problems and is also economically disadvantageous.

This invention was made with the aim of improving this problem, and provides an automatic ultrasonic flaw detection device that can prevent mechanical damage to the probe holding mechanism without installing a new plate edge detection sensor. The purpose is to

[Means for solving problems]

The automatic ultrasonic flaw detection device according to the present invention utilizes the monitoring function of the acoustic coupling state of the probe, which is commonly implemented in this type of device, adds a certain logical judgment to the coupling check signal, and calculates the result. Therefore, the contact plate drive circuit of the probe holding mechanism is interlocked.

[Effect]

In the automatic ultrasonic flaw detection device according to the present invention, if the acoustic coupling state of the probe is poor at the tip or side edge of the plate, the contact plate may be mechanically defective or the probe may pop out from the edge of the plate. As a result, the corresponding probe holding mechanism is immediately released.

〔Example〕

FIG. 1 is a block diagram of an automatic ultrasonic flaw detection device showing an embodiment of the present invention. In the figure, (1) is a probe holding mechanism that houses the probe U, (2) is a steel plate (cross section is shown), and +61 is a cylinder for bringing the probe holding mechanism into contact with or separating from the plate. (7) is a transmitting/receiving circuit that transmits electric pulses to the probe υ housed in the probe holding mechanism (1) and receives electric signals from the probe U; ) is a data processing circuit that receives signals from the transmitter/receiver circuit (7) and processes the results of flaw detection, and externally outputs the processing results FO.
Output. (9) is an acoustic coupling check circuit which receives a signal from the transmitter/receiver circuit (7), judges the acoustic coupling state, and generates an output CN'lr as a coupling check result; Ql is an acoustic coupling check circuit (9) according to the present invention; ) is a logic judgment circuit that outputs a result determined by a certain logic in response to a coupling check signal CN from ); (11) is a circuit that receives a control signal D1 for the probe holding mechanism (1) from the outside and connects or separates the probe; The figure shows a drive circuit which has the role of outputting the drive command and interlocking the above drive command based on the judgment signal DN from the logic judgment circuit a. The operation according to the present invention will be explained in detail below with reference to this block diagram.

In the configuration shown in FIG. 1, if the probe holding mechanism (11 is
The plate is now in a state of contact as shown in Figure 4.

If the steel plate (2) begins to come off as shown in Figure 5a, the couplant that was interposed between the probe U and the steel plate (2) under normal contact conditions may be removed. is cut off. As a result, the reflected echoes of the ultrasonic waves generated from the probe U do not return, resulting in poor acoustic coupling. A general automatic ultrasonic flaw detection apparatus has a mechanism for checking such a poor acoustic coupling state using a received signal from the probe U in order to confirm the reliability of the flaw detection results. As shown in FIG. 1, this invention consists in using this coupling check signal CN to prevent mechanical damage in the probe holding + IA structure (11).Specifically, the acoustic coupling failure signal CN is used for logical judgment. As a result, if there is a risk of damage, a release command is sent to the drive circuit (Iυ) of the holding mechanism.

The function of the above logical judgment circuit σ value is 1. Distinguish between the normally occurring acoustic coupling failure and the acoustic coupling failure caused by mechanical probe failure at the edge of the steel plate shown in Figures 4 and 5. Therefore, some ingenuity is required. For example, the conditions for outputting a separation command are when acoustic coupling failure occurs continuously for a certain period of time, when multiple probe holding mechanisms simultaneously fail when contacting the tip of a steel plate, or when a failure occurs at the side edge of a steel plate. For example, the probe holding mechanism is limited to the outermost position of the rear plate.

A specific configuration example for realizing the logic judgment circuit 01 as described above is shown in FIG.

In FIG. 2, (10a) is a plurality of poor coupling signals CNI from the acoustic coupling check circuit 9) of FIG.
1. .

The AND circuit (10b) receives the output of the AND circuit (10a) and performs a logical product upon receiving CNn, and determines the continuity of a certain period of time.As a result, the probe holding mechanism drive circuit shown in FIG. This is to output a release command DN to αυ. The above coupling failure signals CN1...CNn are event signals that turn ON when there is a coupling failure, and CN1...
If all of CNn have poor coupling and this condition continues for a certain period of time, a separation command is issued as an output. 0 Coupling defect signal CN1... CNn is 9 For example, the side edge of the steel plate to be flawed. It is appropriate to adopt the acoustic coupling check results of the probes located on the outside of the probes included in the probe holding mechanism located in the probe holding mechanism.

〔Effect of the invention〕

This invention utilizes the acoustic coupling check function generally provided in automatic ultrasonic flaw detection equipment as explained above.
By outputting a release command to the probe holding mechanism based on a certain judgment when a coupling failure occurs.

This makes it possible to easily prevent damage to the probe and the probe holding mechanism due to malfunction or skew movement when contacting the steel plate.

[Brief explanation of drawings]

Fig. 1 is a block diagram of an ultrasonic flaw detection device showing an embodiment of the present invention, Fig. 2 is a configuration diagram of the logic judgment circuit shown in Fig. 1, and Figs. 3 to 5 are ultrasonic automatic flaw detection for thick steel plates. FIG. 6 is a diagram showing a state of scraping of the probe holding mechanism in the device. In the figure, (1) is the probe holding mechanism, and (2) is the thick steel plate. (6) is a drive device, (7) is a transmitting/receiving circuit, (9) is an acoustic coupling check circuit, QQ is a logic judgment circuit, aυ is a probe holding mechanism drive circuit, and υ is an ultrasonic probe. In FIG. 2, the same or corresponding parts are designated by the same reference numerals.

Claims (1)

[Claims] The acoustic coupling state of each probe is monitored in an automatic ultrasonic flaw detection system that inspects a plate material being conveyed on a conveyance line by repeatedly touching and separating an ultrasonic probe held in a probe holding mechanism. an acoustic coupling check circuit that determines whether to release the probe holding mechanism in response to a coupling check signal from the acoustic coupling check circuit; 1. An automatic ultrasonic flaw detection device comprising means for separating a holding mechanism.