JPH0561591B2 - - Google Patents

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a calibration device for an ultrasonic measuring device, and more particularly, to a calibration device that can be used as a reference device for an ultrasonic flaw detection device. .

[Prior Art] In an ultrasonic flaw detection device, which is one type of ultrasonic measurement device, an A-scope image of the received echo signal is displayed on a CRT display, etc., and the distance to the defect and the board are determined from the position information on the displayed image. I'm looking for thickness, but
In this kind of ultrasonic flaw detection equipment, during measurement,
The device is calibrated to maintain an accurate relationship between the displayed position of the echo received signal and the actual measured distance.

In other words, in ultrasonic measurement devices that perform measurements using images displayed on a display, the time generation circuit that provides horizontal axis information for the measured value is generally constructed of analog circuits such as transistors and ICs, so temperature In order to accurately measure the distance between the plate thickness and the plate thickness due to drift development such as drift due to voltage fluctuations, it is necessary to calibrate in advance with a standard test piece and, if necessary, make fine adjustments using a variable resistor, etc. This is because it is necessary.

For example, as shown in FIG. 3, this calibration is carried out by bringing the probe 2 into contact with a standard test piece 1 whose plate thickness dmm is accurately known, and using the ultrasonic flaw detector 4a of the ultrasonic flaw detector 3 to detect the Adding the transmission path signal T to child 2,
For the echo received by the probe 2, an echo reception signal is obtained, information on the A scope image is generated from the echo reception signal, and this is added to the display device 4b. This is done by displaying a scope image, observing and adjusting the image at that time. The image on the display device 4b at this time is, for example, as shown in FIG. 4.

In the same figure, T is the transmission pulse signal (waveform)
, B ₁ is the received signal (waveform) of the first echo (primary reflected wave) at the bottom surface, and B ₂ is the received signal (waveform of the second echo (secondary reflected wave)) at the bottom surface. ). If we display the respective echo reception signals for such primary and secondary reflected waves, the distance between the echo reception signal B ₁ and the echo reception signal B ₂ at this time corresponds to dmm, and at this time By making the display relationship correspond to the distance dmm, the ultrasonic flaw detection device 3 can be accurately calibrated.

[Problems to be Solved] However, in such a calibration method, when the object to be tested becomes large, unless a test piece of a corresponding size is used, the calibration error becomes large and sufficient calibration cannot be performed. Therefore, a large standard test piece that corresponds to the size of the test object is required. Furthermore, when performing various tests, there is an inconvenience in that a large number of standard test pieces must be prepared accordingly.

On the other hand, due to differences in the primary reflected waves of the object to be measured, tests are also conducted on the characteristics of the object.
In such a case, the positions of the primary reflected waves appear close to each other, so more accurate calibration is required.

For example, considering the measurement of the axial force of a bolt as a mechanical component, as shown in Figure 5, the ultrasonic wave from the probe 2 that is in contact with the head of the bolt 5 is reflected from the bottom of the bolt. The axial force is measured using the fact that the propagation time changes slightly due to stress.In this case, the A scope image is shown in Figure 6. As shown in , if the propagation time from the transmitted pulse signal T to the received echo signal _B1 is t, the propagation time t of the ultrasonic wave when the bolt length is 50 mm is approximately 17 μs.
It will be about. However, when a certain amount of stress is applied to this bolt 5, the echo reception signal B ₁ changes to the position of the echo reception signal B ₁ ′, but the time change Δt is about 0.3 μs at maximum. It's only a matter of degree. When this 0.3 μs is observed on a display screen, it becomes only about 1 mm.

Therefore, the ultrasonic measuring device that performs such tests needs to be accurately calibrated to be able to distinguish this 1 mm difference. For this purpose, standard test pieces, for example, one with a thickness of 50 mm and one with a thickness of 51 mm are prepared and calibrated. Therefore, a large number of test pieces are required depending on the length of the bolt. Therefore, the time and effort required for calibration is also great.

The present invention solves the problems of the prior art, and aims to provide a calibration device for an ultrasonic measuring device that can calibrate the ultrasonic measuring device without using a standard test piece. shall be.

[Means for Solving the Problems] The configuration of the calibration device for an ultrasonic measuring device according to the present invention to achieve such an object is such that a calibration device for an ultrasonic measuring device is connected to a terminal to which a probe of the ultrasonic measuring device is connected. a clock signal generation circuit that receives the clock signal and counts the clock signal up to a first target value in response to a transmission pulse signal sent from the ultrasonic measuring device to the connection terminal. a first time counting circuit that generates a first output signal; and a first time counting circuit that counts the clock signal to a second target value and generates a second output signal in response to the first output signal or the transmitted pulse signal. a second time counting circuit; and a pulse signal generating circuit that sends a pulse signal corresponding to an echo reception signal to the ultrasonic measuring device to the connection terminal in accordance with each of the first and second output signals, and The first target value and the second target value can be set respectively.

[Function] As described above, the calibration device includes a plurality of time count circuits that count the set time according to the transmission pulse signal generated from the ultrasonic measuring device, and a plurality of time count circuits that count the set time when the set time comes. By providing a pulse signal generation circuit that is driven by the ultrasonic measuring device to generate a pulse signal corresponding to the echo reception signal, the calibration device side can generate a standard signal in response to the transmitted pulse signal from the ultrasonic measuring device side. A plurality of pseudo echo reception signals corresponding to the state in which the test piece is measured can be generated at any timing.

As a result, there is no need to carry around standard test pieces for ultrasonic flaw detection, etc., and it is easy to detect and correct the time axis drift peculiar to analog circuits and calibrate the measurement range.
Furthermore, there is no need to use large calibration test pieces when measuring long objects or large objects.

[Example] Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram of a calibration device for an ultrasonic measuring device according to an embodiment of the present invention, and FIG. 2 is an explanatory diagram of display waveforms showing the time relationship of its output signals. Note that components equivalent to those shown in FIG. 3 are designated by the same reference numerals.

6 is a calibration device for the ultrasonic measurement device 3, which is connected to the probe connection terminal 3a of the ultrasonic flaw detector 4a of the ultrasonic measurement device 3, and receives a transmission pulse signal from the ultrasonic flaw detection device 3; Generates a pseudo-ultrasonic reception echo signal similar to that of a standard test piece. Input/output terminal 7 is a terminal for this connection.

This calibration device 6 includes an attenuator 8 that attenuates the transmitted pulse signal, a detection circuit 9 that detects the attenuated waveform and generates a pulse signal of a constant gate logic level, and a clock signal ( a clock signal generating circuit 11 that generates a time pulse signal; time counting circuits 21, 22, and 23.

Furthermore, the calibration device 6 sends and sets count target values (hereinafter referred to as target values) to the counters of the first, second, and third time counter circuits 21, 22, and 23, respectively. , an input device 20 having a keyboard, etc., for specifying the standard test piece to be adopted and setting various measurement conditions for the arithmetic processing unit 19; and displaying the contents of the specified standard test piece and input measurement conditions, etc. The output signals from the display 24 and the first, second, and third time counting circuits 21, 22, and 23 are ORed.
The pulse generation circuit 18 receives the pulses via the circuit 17.

Here, the first time count circuit 21 is composed of a gate circuit 10 and a counter 12,
The gate circuit 10 transmits the gate signal to the detection circuit 9.
The second time counting circuit 22 is composed of a gate circuit 13 and a counter 14, and the gate circuit 12 receives the gate signal from the counter 12 and opens its gate. Further, the third time count circuit 23 is composed of a gate circuit 15 and a counter 16, and the gate circuit 15 receives the gate signal from the counter 14 and opens its gate. Note that the gates of the gate circuits 10, 13, and 15 are closed by the outputs from the respective counters 12, 14, and 16, respectively.

The pulse generation circuit 18 includes counters 12, 14,
In response to these outputs, the probe 2 generates a pseudo echo reception signal corresponding to the echo reception signal generated by the probe 2 as a pulse signal, and sends it to the input/output terminal 7. Then, the probe 2 is attached to the ultrasonic flaw detector 4a of the ultrasonic measurement device 3.
Output as received echo signal from.

The counters 12, 14, and 16 are composed of preset counters or ordinary counters, and are of the type in which a target value is preset and then decremented. That is, each of the counters 12, 14, and 16 is placed in a down-count state, and the set value is subtracted by the input signal, and when the count reaches zero, a count end signal is output. Note that each target value set in each of the counts is set as a count number by the arithmetic unit 19.

In this case, the counters 12, 14, and 16 may each be configured as a counter circuit consisting of a target value counter, a pulse counter for counting a clock signal, and a comparison circuit for comparing the values of each of these counters. In that case, a target value is set in each target value counter from the arithmetic processing unit 19, the pulse counter counts the clock signal input through the gate circuit, and the values of these two counters are compared to find a match. is detected by a comparison circuit, and the matching signal is used as an output signal.

The arithmetic device 19 includes a microprocessor, a memory, an interface, etc., and an input device 20.
Receives information such as target values sent from the A target value is calculated and each counter 12, 14, 16 is set to the designated target value.

Next, to explain its overall operation, first,
The count number corresponding to a certain target value is output from the arithmetic unit 19 as signals j, k, l, and set in each counter 12, 14, 16. In this state,
When a transmission pulse signal is input from the ultrasonic flaw detector 4a to the calibration device 6 via the input/output terminal 7, the input signal pulse signal is attenuated by the attenuator 8 with high input impedance, thereby affecting the flaw detection. do not have.
When the output of the attenuator 8 is applied to the detection circuit 9, the presence of the transmission pulse signal is detected, and the detection output of the detection circuit 9 is applied to the gate circuit 10.

As a result, the gate circuit 10 is opened and the clock signal generator 11 applied to the gate circuit 10
The clock signal output a of the gate circuit 10 is passed through, and the clock signal output c is applied to the counter 12 from the gate circuit 10. Therefore, the counter 12 counts the number of clock signals. The target value of the count number is set in advance in the counter 12 by the signal j from the arithmetic processing unit 19, so when it is decremented and the count number of the set value (target value) becomes zero, the count is stopped. A termination signal d is output.

The count end signal d of the counter 12 is applied to the gate circuit 10 to close its gate, and simultaneously applied to the next gate circuit 13 to open the gate of the gate circuit 13. In the gate circuit 13,
Since the clock signal output a of the clock signal generator 11 is applied, when the gate of the gate circuit 13 is opened, the clock signal e is applied from the gate circuit 13 to the counter 14, and the set value k from the arithmetic unit 19 is applied.
When the count has been counted down by the number of counts, the count end signal f is outputted in the same manner as described above.

The count end signal f of the counter 14 is applied to the gate circuit 13, which closes the gate, and is also applied to the gate circuit 15. Therefore, the gate of the gate circuit 15 is opened, and the clock signal output a of the clock signal generator 11 is also applied to the gate circuit 15, so that the clock signal g is applied to the gate circuit 15 only while this gate is open. When the output is added to the counter 16 and counted down by the set value l from the arithmetic unit 19, a count end signal h is output. Then, it is applied to the gate circuit 15 and the gate is closed.

In this way, when the transmission pulse signal is applied to the input/output terminal 7, the counter 12 starts counting, and after a time determined from the clock frequency of the clock signal generator 11 and the set count number of the setting signal j, A count end signal d is output.Similarly, a count end signal f is output after a time determined from the set count number of the next setting signal k, and then the set count number of the next setting signal l is output. A count end signal h for a time determined from is output.

Count end signals d, f, h of each counter 12, 14, 16 are applied to an OR circuit 17,
The output of the circuit 17 is applied to a pulse generating circuit 18, and a predetermined pulse signal is applied to the input/output terminal 7 in accordance with the generation timing of the count end signals d, f, h. Then, these are transmitted to the ultrasonic flaw detector 4a via the input/output terminal 7, the ultrasonic flaw detector 4a receives them as echo reception signals, and displays them as an A scope image on the display device 4.
b displays.

Here, the final count end signal h is also applied to the arithmetic processing unit 19. Arithmetic processing unit 19
When receiving this signal, counters 12, 14,
Assuming that all counters 16 have finished counting, each target value is set again for each counter 12, 14, and 16. Note that when the counters 12, 14, and 16 are constructed as a preset counter or a counter circuit consisting of a pulse counter for counting a clock signal, a target value counter, and a comparison circuit, it is not necessary to reset the target value.

As a result of the above, the first pulse signal for the first calibration is output from the pulse generation circuit 18 after a time determined by the first set count value (signal j) from the transmission pulse signal of the ultrasonic flaw detection device 3, and subsequently the second pulse signal is output from the pulse generation circuit 18. The next pulse signal for second calibration is output from the pulse generation circuit 18 after a time determined by the set count value (signal k), and subsequently, the third pulse signal is output after a time determined by the third set count value (signal l). A calibration pulse signal is output from the pulse generation circuit 18.

In addition, from the input device 20, time information or thickness information corresponding to each target value, selection data of oblique flaw detection or vertical flaw detection, data specifying a standard test piece, information such as current temperature, sound speed, etc. is input, and the arithmetic processing unit 19, which receives this information, searches the table stored in the memory for time information, etc. for the selected oblique flaw detection or vertical flaw detection of the standard test piece at the standard temperature. , the temperature is corrected according to the input temperature, and the pulse count number is calculated from the pulse generation period of the clock signal generation circuit 11. The value calculated in this way is transferred to the corresponding counter 12, 1 as the target value.
Set to 4,16. On the other hand, these input data, time information, etc. are displayed on a liquid crystal or CRT display 24.

Here, the timing at which each gate circuit opens and closes after the transmission pulse signal T is generated is determined by the target value set in each counter 12, 14, 16, and each target value is specified by the input device 20. It can be selectively set according to the standard test piece used or the input value from the keyboard.

Therefore, by setting the time corresponding to each target value using the input device 20, the calibration device 6 can sequentially generate calibration pulse signals as received echo signals at an arbitrary time after the transmission pulse signal T is generated. In response to this, the measurement screen of the ultrasonic measuring device 3 can be calibrated. Moreover, if the transmission pulse signal is periodically applied from the ultrasonic flaw detector 4a to the calibration device 6, the pulse generation circuit 18 periodically generates a pseudo echo reception signal corresponding to the generation cycle of the transmission pulse signal T. is ultrasonic flaw detection device 3
will be sent to.

Here, the arithmetic processing device 19 calculates each of the target values described above under the conditions set by the input device 20. For example, if the set value of the counter 12 is x, each of the set values The relationship between the target value and time is expressed by the following equation.

x = (set distance value from input device) x 2
/(Sound speed set at the input section) x (clock signal frequency) Therefore, the input device 20 causes the counter 1 to
It is sufficient to set three set distances corresponding to 2, 14, and 16 and the sound speed.

As shown in Fig. 2, the first pulse signal generated from the pulse generation circuit 18 in response to the transmission pulse signal T is _C1 , its time setting value is _x1 , the next pulse signal is _C2 , and the time Assuming that the set value is x ₂ , the next pulse signal is C ₃ , and the time set value is x ₃ , these values become the timing at which the count end signals d, f, and h of each counter are generated.

Therefore, if we apply this to the case of setting the bolt shown in Fig. 5, the pulse signal _C1 will correspond to the echo reception signal of the signal (surface reflected wave) in which the transmitted pulse signal is reflected at the bolt head. The pulse signal C ₂ can be made to correspond to the echo reception signal of the reflected wave at the bottom of the bolt when no stress is applied to the bolt, and the pulse signal
C ₃ can be made to correspond to the echo reception signal of the reflected wave at the bottom of the bolt when stress is applied to the bolt, and by generating each pulse signal C ₁ , C ₂ , C ₃ , the ultrasonic measuring device 3 can be calibrated under conditions close to the measurement conditions.

In this case, pulse signal C ₂ is set slightly before the position of the echo from the actual bottom of the bolt, and pulse signal C ₃ is set slightly after the position of the echo from the actual bottom of the bolt. There is. Therefore, the waveforms from a little earlier to a little later are displayed on the screen of the CRT display of the display device 4b, and the time scale (or distance scale) between them can be accurately calibrated.

The time setting value x ₁ which gives the calibration time in this way,
Freely select x ₂ and x ₃ according to the object to be measured, set the positions of the generated pulse signals C ₁ , C ₂ , and C ₃ to the optimal calibration positions according to the object to be measured, and then start the device. Can be calibrated and measured.

For example, let x ₁ (dead band time) be the ultrasonic propagation time from the diaphragm of probe 2 to the surface of probe 2, that is, the surface of the object, and then calculate the generation position of the echo reception signal corresponding to the bolt length. Set _the ultrasonic propagation time x ₂ corresponding to the front of By determining this, accurate calibration can be made to correspond to the amount of change when stress is applied to the bolt, and measurements can be made under that amount.

In addition, in this case, three of the pulse signals C ₁ , C ₂ , and C ₃
Although one output signal is sent out from the calibration device 6, it is also possible to ignore the dead zone time and not output the pulse signal _C1 . In such a case, the pulse signal _C2 will be output for a set time that is the sum of the time set values _x1 and _x2 . To do this, the counter 12 and the gate circuit 13 may be omitted or their operation may be stopped, and the gate circuit 1
The clock signal output c of 0 is input to the counter 14, and the clock signal is counted. The set value of the counter 14 at this time is x ₁ +x ₂ . Also,
It is also possible to simply prevent the counter end signal j of the counter 12 from being input to the OR circuit 17 while leaving the time setting values of the counters 12, 14, and 16 as they are.

Note that, as described above, the first time count circuit 2
1 count and without providing the gate circuit 13 of the second time counting circuit 22, the clock signal output of the gate circuit 10 is added to the counter 14 of the second time counting circuit 22, and the count end signal f is used to count the first time. Although the gate of the gate circuit 10 of the count circuit 21 may be closed, it is also possible to omit the third time count circuit 23 and use the first time count circuit 21 as it is as the second time count circuit 22. The counter 12 is used to set the time to the value x ₁ + x ₂ , and the second time count circuit 2
The same effect can be obtained by using the circuit 2 as is as the third time counting circuit 23 and setting the time to the value of x ₃ in the counter 14.

Here, since the time setting value x ₁ corresponds to a very short distance, the higher the frequency of the clock signal, the better; however, for the setting time values x ₂ and x ₃ , the frequency of the clock signal does not need to be high. . Therefore, two clock signal frequencies, one high and one low, can be used. This can be easily obtained by dividing a high frequency clock signal with a divider (or frequency divider), so that the gate circuit 10 receives a high frequency clock signal, and the gate circuits 13 and 15 receive a low frequency clock signal. This can be achieved by adding the following and selecting the frequency of each clock signal. At this time, a high frequency clock signal may also be applied to the gate circuit 15 side.

In this way, by lowering the frequency handled, the number of circuits used, especially the number of ICs used, can be reduced.
It also has the advantage of being able to use low-speed and inexpensive ICs.
Moreover, in this way, the first time count circuit 21
, the second and third time counting circuits 22 and 23
By counting using a faster clock signal, the distance of the dead zone of the probe can be set more precisely.

In the embodiment, since an input device 20 is provided, the first set value, the second set value, and the third set value are inputted in units of length using this input device 20, and the input device 20 is used to input the first set value, the second set value, and the third set value in length units. The sonic speed setting value is used to convert into a unit of time by an arithmetic processing unit, and the first, second, and third time counting circuits 21 and 2 respectively
It is possible to calculate the respective setting values of 2 and 23, but in addition, only the first setting value is input as a unit of time, and the second setting value and the third setting value are input as a unit of length. Then, input the set value of the sound speed at that time, use this set value of the sound speed to convert the set value of the length unit into the unit of time, and calculate the first, second, and third values, respectively. time count circuit 21,
It can also be set to 22 or 23.

Therefore, the input device 20 has a time setting value.
There will be settings for x ₁ , x ₂ , x ₃ and a key to set the ultrasonic sound speed, but for example, if the measurement target is limited to steel, the sound speed setting can be omitted and the sound speed set to 5900.
Calculation can also be performed assuming that m/s is constant. Also,
Since there are other types of measurement that assume the speed of sound is constant, it is possible to set the speed of sound to a constant value and not input it. In such a case, give the second setting value and the third setting value in units of length,
A preset value of the sound speed may be used to convert into a unit of time by an arithmetic processing device and set in the first, second, and third time counting circuits, respectively.

Furthermore, when temperature is involved, such as when bolt stress is measured at different ambient temperatures, the temperature at that time or a temperature coefficient can be input to calculate the bolt elongation due to temperature. It can also be processed with a processing device. That is,
If the temperature of the test object is different from that of the standard specimen,
Measurement errors occur due to elongation due to temperature, but by setting the temperature and temperature coefficient, correction calculations can be made and calibration can be performed to ensure accurate measurements.

As explained above, the arithmetic processing device in the embodiment does not use a microprocessor, but instead uses other processors.
It may also be composed of parts such as ICs.

The counting of each time counting circuit may be any method that outputs a count end signal after counting a set count number, and various circuits such as countdown or countup can be easily configured. It goes without saying that counting down the counter from a set value and generating an output when it reaches zero also corresponds to counting up to the target value in the present invention.

The setting of the input device may be such that the time is calculated from the length setting, or the time may be directly set and the length may be calculated and displayed. Especially the first
Since the set value of the counter can be used as the propagation time within the probe, it is constant regardless of the sound speed of the test object, so it may be better to set the time.

In addition, in the example, the case of the one-probe method was explained, and the input of the transmission timing and the signal output for calibration were made into the same terminal, but in the case of the two-probe method, these were made into separate terminals, The transmitting terminal of the ultrasonic flaw detector may be connected to the transmission timing connection terminal, and the receiving terminal of the ultrasonic flaw detector may be connected to the signal output terminal for calibration.

In the embodiment, three time counting circuits are provided, each consisting of a gate circuit and a counter,
The output signal of the counter of the first time counting circuit is supplied to the gate circuit of the second time counting circuit, and the output signal of the second counting circuit is supplied to the third gate circuit, so that they are sequentially connected. However, the gate signals of the first, second, and third gate circuits may be obtained in correspondence with the transmission pulse signal, and these may be arranged in parallel and counted in parallel. The time setting value in such a case is that if the counter of the first time counting circuit is x ₁ , the counter of the second time counting circuit is x ₁ + x ₂ , and in the third, x ₁ + x ₂ + x ₃ And it is sufficient.

Note that, as in the embodiment, if the second and/or third gate circuit is gated by the output of the counter of the first time counting circuit, it is convenient when setting the dead zone.

[Effects of the Invention] As can be understood from the above description, the present invention includes a plurality of time counting circuits that count time set according to a transmission pulse signal generated from an ultrasonic measurement device as a calibration device. Ultrasonic measurement is possible by providing a pulse signal generation circuit that is driven by a plurality of time counter circuits and generates a pulse signal corresponding to the echo reception signal in the ultrasonic measurement device when a set time comes. A plurality of pseudo echo reception signals corresponding to the state in which a standard test piece is measured can be generated from the calibration device side at an arbitrary timing in response to a transmission pulse signal from the device side.

As a result, there is no need to carry around standard test pieces for ultrasonic flaw detection, etc., and it is easy to detect and correct the time axis drift peculiar to analog circuits and calibrate the measurement range.
Furthermore, there is no need to use large calibration test pieces when measuring long objects or large objects.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a calibration device for an ultrasonic measurement device according to an embodiment of the present invention, FIG. 2 is an explanatory diagram of a display waveform showing a time function of the output signal, and FIG. A conceptual diagram showing the calibration method using a conventional standard test piece. Figure 4 is an explanatory diagram of the display state of the ultrasonic flaw detector during calibration using a conventional standard test piece. Figure 5 is FIG. 6 is an explanatory diagram showing the state of propagation of ultrasonic waves in FIG. 6. FIG. 6 is an explanatory diagram showing the time relationship of ultrasonic echo signals when no stress is applied to the bolt and when stress is applied to the bolt. 1...Standard test piece, 2...Probe, 3...Ultrasonic measuring device, 4a...Ultrasonic flaw detection device, 4b...
Display device, 5... Volt, 6... Calibration device, 7...
...Input/output terminal, 8...Attenuator, 9...Detection circuit, 10,13,15...Gate circuit, 12,1
4, 16...Counter, 17...OR circuit, 18
... Pulse generation circuit, 19 ... Arithmetic processing unit, 2
0...Input device, 21...First time counting circuit, 22...Second time counting circuit, 23...
Third time counting circuit, 24...display.

Claims (1)

[Scope of Claims] 1. A connection terminal connected to a terminal to which a probe of an ultrasonic measuring device is connected, a clock signal generation circuit that generates a clock signal, and a clock signal generating circuit that receives the clock signal and connects the ultrasonic measuring device. a first time counting circuit that counts the clock signal up to a first target value and generates a first output signal in response to a transmission pulse signal sent to the connection terminal from the clock signal;
a second time counting circuit that counts the clock signal up to a second target value and generates a second output signal according to the output signal of the clock signal or the transmission pulse signal; and a first and second output signal, respectively. a pulse signal generating circuit that sends a pulse signal corresponding to an echo reception signal to the ultrasonic measuring device to the connection terminal in accordance with the first target value and the second target value.
A calibration device for an ultrasonic measuring device, characterized in that target values of can be set respectively. 2. The first and second target values are set by an arithmetic processing device as values corresponding to designated standard test pieces, respectively. Calibration device. 3. The first and second time counting circuits each include a gate circuit and a counter that counts up to a target value, and each gate circuit receives a clock signal from the clock signal generation circuit and
The gate circuit of the time counting circuit opens the gate in response to the detection of the transmission pulse signal and supplies the clock signal to the counter of the first time counting circuit; Claim 2, characterized in that the gate is opened in response to an output signal when the counter of the second time counting circuit counts up to a target value, and a clock signal is supplied to the counter of the second time counting circuit. Calibration device for ultrasonic measurement equipment. 4. The second time counting circuit is composed of a plurality of time counting circuits each including a gate circuit and a counter that counts up to a target value, and a target value is set for each of the counters, and one of the plurality of time counting circuits is The output signal of the counter of one time counting circuit is supplied as a gate signal to the gate circuit of another time counting circuit, and each gate circuit receives the clock signal and supplies the clock signal to the counter of the corresponding time counting circuit. and wherein each of the output signals of the counter of each of the time counting circuits is sent to a pulse signal generation circuit to generate a pulse signal corresponding to an echo reception signal. Calibration device for sonic measuring devices.