JPH0614030B2 - Origin setting device for ultrasonic flaw detector - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an ultrasonic flaw detector origin setting device that determines an origin in a display unit that displays a waveform in an ultrasonic flaw detector.

[Conventional technology]

The ultrasonic flaw detector is well known as an apparatus for inspecting the presence or absence of a flaw inside an object without destroying the object. This ultrasonic flaw detector will be described with reference to the drawings.

FIG. 7 is a block diagram of a conventional ultrasonic flaw detector. In the figure, 1 indicates an object to be inspected and 1f indicates a defect existing in the object to be inspected 1. Reference numeral 2 denotes an ultrasonic probe that radiates ultrasonic waves into the inspection object 1 and outputs an electric signal proportional to the reflected ultrasonic waves. An ultrasonic flaw detector 3 outputs an ultrasonic wave generation pulse to the ultrasonic probe 2, receives a signal from the ultrasonic probe 2, and displays the waveform of this signal.

The ultrasonic flaw detector 3 is composed of the following elements. That is,
Reference numeral 4 is a synchronizing circuit for generating a signal voltage for timely controlling the operation of the ultrasonic flaw detector 3, and 5 is a transmitter for outputting a pulse for generating ultrasonic waves to the ultrasonic probe 2 in response to a signal from the synchronizing circuit 4. Is. Reference numeral 6'denotes a receiving unit for receiving a signal from the ultrasonic probe 2, and is composed of an attenuation circuit 6a composed of a combination of voltage dividers composed of resistors, and an amplification circuit 6b '. Reference numeral 7 is a detector circuit for rectifying the signal from the amplifier circuit 6b ', and 8 is a vertical axis amplifier circuit.

Reference numeral 9 is a sweep circuit for generating a triangular wave by the synchronizing signal from the synchronizing circuit 4, and 10 is an amplifier circuit for amplifying the triangular wave signal of the sweep circuit 9. Reference numeral 11 is a display unit for displaying a signal waveform from the ultrasonic probe 2, the horizontal axis is a time axis determined by the triangular wave output from the amplifier circuit 10, and the vertical axis is output from the vertical axis amplifier circuit 8. It is regarded as the size of the signal. Display 11
A cathode ray tube is used as a display, and a scale is displayed on its surface. A measurement range setting unit 12 sets a range (measurement range) to be inspected from the surface of the inspected object 1. Reference numeral 13 denotes a delay time setting unit that adds a delay time to the sweep start signal and moves the position of the waveform displayed on the display unit 11 in parallel.

Next, an outline of the operation of the conventional ultrasonic flaw detector will be described. When a pulse is output from the transmitter 5 by the signal voltage from the synchronous rotation 4, the ultrasonic probe 2 is excited by this pulse and radiates ultrasonic waves to the inspected object 1. Part of the emitted ultrasonic waves immediately returns to the ultrasonic probe 2 from the surface of the inspected object 1, and the other propagates in the inspected object 1.
It reaches the bottom of the object to be inspected 1, is reflected here, and returns to the ultrasonic probe 2. On the other hand, if the defect 1f exists in the inspected object 1, the ultrasonic waves are reflected also at the defect 1f and return to the ultrasonic probe 2. The ultrasonic waves returned to the ultrasonic probe 2 excite the ultrasonic probe 2 in proportion to its size, and the ultrasonic probe 2 outputs an electric signal corresponding thereto.

This signal is input to the attenuation circuit 6a, adjusted to a size suitable for processing, and input to the detection circuit 7 via the amplification circuit 6b '. The detection circuit 7 rectifies the input signal in order to direct the display on the display unit 11 to make a one-sided swing instruction. At this time, the noise component mixed in the signal is also removed. The output signal of the detection circuit 7 is input to the display unit 11 via the vertical axis amplification circuit 8 and its magnitude is shown on the vertical axis of the display unit 11. On the other hand, the sweep circuit 9 generates a triangular wave voltage by the synchronizing signal of the synchronizing circuit 4, and this voltage is applied to the deflection electrode of the display unit 11 (cathode ray tube) via the amplifier circuit 10 to sweep the electron beam. By this sweep and the input signal from the vertical axis amplifier circuit 8,
The display unit 11 displays the waveforms of the two reflected reflected waves of the ultrasonic probe.

In flaw detection using such an ultrasonic flaw detector 3, the waveform of the reflected wave displayed on the display unit 11 changes depending on the contact state between the inspected object 1 and the ultrasonic probe 2. In order to avoid this, the water immersion method is usually adopted. 8th
The figure is a cross-sectional view for explaining the water immersion method. In the figure, 1 is an object to be inspected, 1f is a defect, and 2 is an ultrasonic probe, which is the same as that shown in FIG. Reference numeral 15 indicates a water tank, and 16 indicates water in the water tank 15. The inspection object 1 is submerged in the water tank 15, and the ultrasonic probe 2 is opposed to the inspection object 1 via the water 16. The ultrasonic wave from the ultrasonic probe 2 is water 1
Since the reflected wave from each part of the object to be inspected 1 is input to the ultrasonic probe 2 via the water 16, a stable waveform is displayed on the display section 11. Will be.

FIG. 9 is a waveform diagram of the displayed reflected wave. In the figure, the horizontal axis represents time and the vertical axis represents the magnitude of the reflected wave. T is a transmitted reflected wave received by the probe 2 at the same time when the probe 2 transmits an ultrasonic wave, S is a reflected wave from the surface of the inspected object 1, F is a reflected wave from the defect 1f, and B is a reflected wave. A reflected wave from the bottom surface of the inspection object 1 and B _S are reflected waves from the bottom surface of the water tank 15. S _C indicates a scale drawn on the display unit 11, S _L indicates a left end vertical direction scale, and S _R indicates a right end vertical direction scale. Since the sound velocity of ultrasonic waves in the object to be inspected 1 is constant, the horizontal axis represents time (the time axis represents distance).

[Problems to be Solved by the Invention]

The purpose of the ultrasonic flaw detector 3 is to know the presence or absence of a defect, and the position and size of the defect, if any, from the waveform displayed on the display unit 11. The position of the defect is the object to be inspected 1
It is understood as the distance from the surface of.

However, the display unit 11 displays to right from the left end is the waveform shown in FIG. 9, therefore, will be transmitted reflected wave T is displayed on the left end of the scale S _L, the surface reflected wave S and the defect reflected wave F an interval (or distance) between the scale S _C
It becomes difficult to read with. And this scale S _C
To facilitate reading of the left end of the scale S _L
It is necessary to make the peak of the surface reflected wave S coincide with and set it as the origin of the distance.

In order to set such an origin, the conventional ultrasonic flaw detector 3
In the above, while looking at the display surface of the display unit 11, the knob of the delay time setting unit 13 is operated to move the waveform in parallel in the distance axis direction so that the peak of the surface reflected wave S is exactly the left end scale S _L.
Match. This adjustment was very delicate and it was not easy for a beginner to match the two.

By the way, generally, when inspecting the inspection object 1, it is not always necessary to inspect the entire surface from the top surface to the bottom surface.
It is often sufficient to inspect a certain depth range from the surface. In this case, the waveform display is the range (measurement range)
It is desirable that only the display be made, so that more accurate analysis can be performed. The measurement range is set by operating the coarse adjustment knob and the fine adjustment knob of the measurement range setting unit 12 to expand or contract the distance axis, but this adjustment is also delicate and difficult. Then, by setting the measurement range, a large deviation occurs in the previously set origin, and it becomes necessary to set the origin again.

An object of the present invention is to solve the above-mentioned problems of the prior art and to easily and accurately set the origin in waveform display, and the set origin does not change even by other waveform processing operations. An object is to provide an origin setting device for a flaw detector.

[Means for Solving the Problems]

In order to achieve the above object, the present invention provides a transmitter that outputs a predetermined pulse to an ultrasonic probe, a receiver that receives a signal from the ultrasonic probe, and a receiver that receives the signal. In the ultrasonic flaw detector equipped with a display unit for displaying the waveform of the signal based on the signal, a memory for sequentially storing the signals received by the receiving unit at a predetermined sampling cycle, and this memory Peak value searching means for searching each peak value of the stored signal, and an address storing a peak value serving as an origin which is a reference point for finding a defect position among the peak values searched by the peak value searching means. Is set as the origin address, and the signal stored in the memory is set as the origin address of the display unit using the address set by the origin address setting means. Characterized in that a display control means for displaying on the display unit.

[Action]

The reflected wave of the ultrasonic wave from the inspected object returns to the ultrasonic probe, and the ultrasonic probe outputs a signal corresponding to the reflected wave. The receiving unit receives this signal, and the output signal from the receiving unit is sequentially stored in the memory at a predetermined sampling period. Of the peak values of each reflection waveform, the origin is set, that is, a point serving as a reference point for determining a defect position, and an address storing the peak value is set. This set address is used as the address of the origin of the display unit, and the data stored at each address of the memory is displayed on the display unit with this address as a reference.

〔Example〕

 Hereinafter, the present invention will be described based on the illustrated embodiments.

FIG. 1 is a block diagram of an ultrasonic flaw detector according to an embodiment of the present invention. In the figure, the same parts as those shown in FIG. In the ultrasonic flaw detector, there are a case where the reflected wave is detected and displayed and a case where the reflected wave is not detected and displayed, but the present invention can be applied in any case. Therefore, in the following, an embodiment will be described in which the receiver 6 is constituted by combining the amplifier 6b 'of FIG. 7 and the detection circuit 7 as the amplification circuit 6b, and detection is performed. 21
Shows the ultrasonic flaw detector of the present embodiment. This ultrasonic flaw detector 2
1 is composed of the following elements. That is, 22 is an A / D converter that converts the output signal of the receiver 6 into a digital value, 23 is a waveform memory that stores the value converted by the A / D converter 22, and 24 is each address of the waveform memory 23. It is an address counter that is specified in order. Reference numeral 25 denotes a timing circuit, which gives a start signal to the transmitter 5, the A / D converter 22, and the address counter 24, respectively. A crystal oscillator is used for oscillation of the timing circuit 25.

Reference numeral 26 is a CPU (central processing unit) for performing required arithmetic operations and control, 27 is a RAM (random access memory) for temporarily storing parameters and data for arithmetic operations, 28
Is a ROM (read only memory) that stores the processing procedure of the CPU 26. Reference numeral 29 is a measurement range setting unit for inputting a desired measurement range, and 30 is a keyboard input unit for inputting numerical values and the like. Reference numeral 31 is a liquid crystal display unit, and 32 is a display unit controller which controls the display of the liquid crystal display unit 31 based on the data obtained as a result of the calculation and control of the CPU 26.

FIG. 2 is a layout view of the key switches in the keyboard input section shown in FIG. In the present embodiment, the key switches of the keyboard input unit 30 are ten numeric key switches 30 to 0 to 9 and the origin key switch 30b with the indication of "origin" and the set key switch 30c with the indication of "set". It is composed of. The origin key switch 30b has a function of activating a processing operation for obtaining the origin position, and the set key switch 30c has a function of outputting an input end signal.

Next, the operation of the present embodiment is shown in FIG.
This will be described with reference to the contents explanatory view of the waveform memory 23 shown in FIG. 4, the flowchart shown in FIG. 5, and the display waveform diagram of the display section shown in FIGS. 6 (a) and 6 (b). When the trigger signal is output from the timing circuit 25 to the transmitting unit 5, the transmitting unit 5 outputs a pulse to the ultrasonic probe 2, and the ultrasonic probe 2
Ultrasonic waves are radiated from the inside of the inspected object 1. The reflected wave of this ultrasonic wave is converted into an electric signal by the ultrasonic probe 2,
This signal is received by the receiving unit 6. The receiving unit 6 outputs the received reflected wave signal as a value suitable for the subsequent processing.
The output reflected wave signal is converted into a digital value in the A / D converter 22 at a predetermined sampling cycle, and the converted value is sequentially stored in the waveform memory 23. In this storage, the address counter 24 is the waveform memory 2
This is done by sequentially designating addresses of 3. The sampling of the reflected wave signal and the addressing of the waveform memory 23 are performed by a start signal output from the timing circuit 25. The sampling of such a reflected wave signal and the storage of the digital value in the waveform memory 23 will be described with reference to FIGS. 3 and 4.

FIG. 3 is a waveform diagram of the reflected wave signal. In the figure, the horizontal axis represents time, and the vertical axis represents the magnitude (voltage) of the reflected wave signal. T and F show the same reflected waves as shown in FIG. Incidentally, in FIG. 3, only the horizontal axis is drawn in an extremely enlarged manner. Next, FIG. 4 is an explanatory view of the contents of the waveform memory 23. Each block shown in a column is the waveform memory 23.
Means the data accommodating section in D, and D ₍₀₎ , D ₍₁₎ , ... D _(n-1) , D _(n) , D _{(n + 1)} ... described in each accommodating section.
Is data of the reflected wave signal converted into a digital value by the A / D converter 22. D of these data as a general form
Represented by _(i) . In addition, the code A described on the left side of each accommodation portion
_{M (0)} , A _{M (1)} , ……… A _{M (n-1)} , A _{M (n)} , A _{M (n + 1)} ……
... indicates the address of the corresponding accommodation unit. These addresses are represented by A _{M (i)} as a general form.

Now, at the time t ₀ shown in FIG. 3, the timing circuit 2
When a start signal is output from A to D / A converter 22 and address counter 24, A / D converter 22 A / D converts the voltage of reflected wave T at that time to obtain data D ₍₀₎ . . Further, the address counter 24 designates the address A _{M (0)} of the waveform memory 23. As a result, the data D ₍₀₎ is stored in the address A _{M (0)} of the waveform memory 23. Next, at a time t ₁ after the time τ _{S has} elapsed, the timing circuit 25
Again from the A / D converter 22 and the address counter 24
When a start signal is output to, the reflected wave T at that time also
Is the voltage of the conversion by the A / D converter 22 and the data D ₍₁₎ is obtained, since the address counter 24 designates the next address A _{M (1),} the address A _{M (1)} of the waveform memory 23 The data D ₍₁₎ is stored. In this case, the time τ _S becomes the sampling time (for example, 50 ns). In the same manner reflected wave T, S, F, B, data of _{B S} waveform memory 23
Will be stored in.

Next, the operation of setting the origin will be described. When setting the origin, first, the origin key switch 30b of the keyboard input unit 30 is pressed. The CPU 26 always determines whether or not the origin key switch 30b has been pressed (procedure P ₁ shown in FIG. 5), and performs the origin setting process by determining that the origin key switch 30b has been pressed. That is, first, based on the data stored in the waveform memory 23, each reflected wave T,
S, F, B, searches the peak value of _{B S,} obtains the address that stores the peak value (Step _P 2).

Next, each reflected wave T, S, F, B, B _S is displayed on the liquid crystal display unit 31 (procedure P ₃ ). The outline of this display will be described. The liquid crystal display unit 31 has a certain number of liquid crystal dots arranged in the lateral direction, and the display unit controller 32
Is provided with a display memory (not shown) having the same number of addresses as the array. Now, assuming that the number of liquid crystal dots arranged is 200, the number of addresses {represented by AL _(j) } in the display memory is 200 from address _{AL (O)} to address _{AL (199).} . On the other hand, among the addresses A _{M (i)} of the waveform memory 23, the reflected waves T, S, F,
For example, the number of addresses in which B and B _S are stored is 1
000. Since the number of display memories is 200, it is necessary to thin out the data to be displayed in order to display the entire area. Therefore, among the above 1000 addresses {addresses A _{M (O) to} A _{M (999)} }, every fifth address {addresses A _{M (O)} , A _{M (5)} , A _{M (10)} , A _{M ( 990)} } to correspond to the address A _{L (j)} of the display memory, transfer the data to the address of the display memory, and display these data on the liquid crystal display 31 by the display controller 32. ~ B _S can be displayed.

Next, as shown in FIG. 6 (a), all the peak values of the waveform displayed on the liquid crystal display unit 31 are numbered and displayed, and the peak value to be the origin position is selected from the peak values. The origin position selection display for instructing is displayed (procedure P ₄ ). It should be noted that these numbers are sequentially assigned in advance to the respective peak values obtained in the procedure P ₂ . In the case shown in FIG. 6 (a), the reflected wave T, S, F, B, No. 0-4 in order respectively to the peak value of B _S are attached, also as the origin position selection display "home position wo Siji Sina Sai" Is displayed. In accordance with this instruction, the operator presses the peak value number "1" of the reflected wave S on the numeric key switch 30a of the keyboard input unit 30 on which the numeral "1" is displayed, and then the set key switch 30c. Press to signal the end of input.

The CPU 26 sees the instruction from the keyboard input unit 30,
Since this is the number "1", an address {this address is referred to as A _{M (S)} } for storing the peak value of the reflected wave S is taken out from the addresses obtained in the procedure P ₂ (procedure P ₅ ). When the address A _{M (S)} is determined in this way, the address A _{M (S)} stores the first address of the display memory of the display controller 32 (data displayed at the leftmost end of the liquid crystal display 31). Address) A _{L (0)} (procedure P ₆ ). Then, in the display on the liquid crystal display unit 31, the peak value of the reflected wave S is displayed at the leftmost end as shown in FIG. 6 (b), and this is the origin. In order to perform the waveform display as shown in FIG. 6 (b) (parallel movement of the waveform display of FIG. 6 (a)), the waveform memory 23 displaying the waveform shown in FIG. 6 (a) is used. For each of the addresses, the address of the display memory corresponding thereto may be an address obtained by subtracting the number of addresses of the display memory having the first peak value from the correspondence of the display of FIG. 6 (a).

Address A for storing the peak value set as the origin
_{M (S)} is stored in a required address of the RAM 27, for example, and no matter how the subsequent reflection waveform display processing (for example, measurement range setting processing) is performed, the address A _{M (S)} is used as the origin address. Will be retained. Therefore, not only is the origin set easily and accurately, but the origin does not fluctuate no matter what process is performed after the origin is set.

In the description of the above embodiment, an example in which the peak value of each waveform is obtained and the origin is set has been described. However, the present invention is not limited to this, and the origin is set by displaying a cursor on the liquid crystal display unit 31. You can also That is, a rotary switch is separately provided so that all addresses of the display memory can be designated. Then, when an address is designated by this rotary switch, the data stored at the address is changed to data displaying a vertical line or a broken line, and when the designation is released, the cursor means for storing the original data again. Is provided. In this way, with the rotary switch and cursor means installed,
As described above, when each reflected wave is displayed on the liquid crystal display unit 31 and the rotary switch is rotated, a straight line or a broken line on the waveform moves in the horizontal direction as a cursor in response to this. Therefore, by making the cursor coincide with the peak of the reflected wave S, the address A _{M (S)} of the waveform memory 23 corresponding to the address of the display memory at that time can be designated as the origin.

Further, in the description of the above-mentioned embodiments, the liquid crystal display unit is illustrated as the display unit, but the display unit is not limited to the liquid crystal display unit, and it is obvious that a cathode ray tube, a plasma display unit or the like can be used. .

〔The invention's effect〕

As described above, in the present invention, the received reflected wave data is stored in the waveform memory, a predetermined peak value among the peak values of each waveform is designated as the origin, and the address of the peak value is displayed on the display unit. Since the display is performed as the origin of the address, the origin can be set easily and accurately, and the origin does not change even if other processing such as setting the measurement range is performed.

[Brief description of drawings]

FIG. 1 is a block diagram of an ultrasonic flaw detector according to an embodiment of the present invention, FIG. 2 is a layout diagram of key switches of a keyboard input section shown in FIG. 1, and FIG. 3 is a partial waveform diagram of a reflected wave. , FIG. 4 is an explanatory view of the contents of the waveform memory shown in FIG. 1, and FIG.
6 is a flowchart explaining the operation of the ultrasonic flaw detector shown in FIG. 6, FIGS. 6 (a) and 6 (b) are waveform diagrams displayed on the liquid crystal display unit shown in FIG. 1, and FIG. 7 is a conventional ultrasonic flaw detector. Of FIG. 8, FIG. 8 is a sectional view for explaining the water immersion method, and FIG. 9 is a waveform diagram of a reflected wave. 1 ... Object to be inspected, 1f ... Defect, 2 ... Ultrasonic probe, 5 ... Transmitting section, 6 ... Receiving section, 21 ... Ultrasonic flaw detector, 22 ... A / D converting section, 23 ... Waveform memory, 24
...... Address counter, 25 ...... Timing circuit, 26
... CPU, 27 ... RAM, 28 ... ROM, 29 ...
… Measurement range setting section, 30 …… Keyboard input section, 31…
... Liquid crystal display

Claims (1)

[Claims] 1. A transmitting unit that outputs a predetermined pulse to an ultrasonic probe, a receiving unit that receives a signal from the ultrasonic probe, and a receiving unit that is based on the signal received by the receiving unit. In an ultrasonic flaw detector equipped with a display unit that displays the waveform of the signal, a memory that sequentially stores signals received by the receiving unit at a predetermined sampling period, and a signal that is stored in the memory. The peak value searching means for searching each peak value and the address storing the peak value serving as the origin which is the reference point for finding the defect position among the peak values searched by this peak value searching means are set as the origin address. Table for displaying the signal stored in the memory as the origin address setting means and the address set by the origin address setting means as the origin address of the display portion. Origin setting device of the ultrasonic flaw detector, characterized in that a control means.