JPH0720101A - Method and equipment for ultrasonic measurement - Google Patents

Abstract

PURPOSE:To allow application to any object while enhancing the accuracy. CONSTITUTION:The ultrasonic measuring equipment comprises a pulser 62 being actuated by a transmission signal (d) to produce a transmission wave signal (e), a transducer 51 for converting an output from the pulse 62 into am ultrasonic wave U propagating through an object A and receiving the reflected ultrasonic wave U, a comparator 64 producing a receiving signal (g) based on a receiving wave signal (f) from the transducer 51, and a section 65 receiving the transmission signal (d) and the receiving wave signal (g) from the comparator 64 and measuring the propagation signal of ultrasonic wave through the object A. The ultrasonic measuring equipment further comprises a circuit 10 actuated by the transmission signal (d) to switch the output circuit part of the comparator 64 to the input part of the pulser 62, and a counter 13 counting the output pulses from the comparator 64 and switching the circuit 10 to normal connection when a preset count is matched.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic wave measuring method and apparatus for precisely measuring the propagation time of ultrasonic waves in a body to be measured.

[0002]

2. Description of the Related Art FIG. 3 is a block diagram showing a conventional ultrasonic measuring device, and FIG. 4 is a time chart showing the operation of the conventional ultrasonic measuring device. Hereinafter, description will be given based on these figures.

The conventional ultrasonic measuring device operates by being energized by the transmission signal d from the transmission signal generator 61, and transmits the transmission wave signal e.
And a transducer 5 for converting the output from the pulsar 62 into an ultrasonic wave U, propagating the ultrasonic wave U into the measured object A, and receiving the reflected ultrasonic wave from the measured object A.
1, a wideband amplifier 63 that amplifies the received wave signal f output from the transducer 51, and a comparator 64 that outputs a measurement end signal i when the received wave signal f amplified by the wideband amplifier 63 is a predetermined value or more. , The measurement end signal i from the comparator 64 and the transmission signal generator 61
And a time measurement unit 65 that measures the propagation time of the ultrasonic wave in the measurement object A based on the time difference between the measurement start signal c and the measurement start signal c.

Here, when the transmission signal generator 61 outputs the measurement start signal c and the transmission signal d, the time measuring section 65 starts the time measurement, and the transducer 51 outputs the ultrasonic wave U by the output from the pulsar 62. Output to the measuring object A. The received wave signal f from the transducer 51 is
After being amplified by the wide band amplifier 63, a signal is output from the comparator 64 if the voltage value is equal to or higher than a predetermined value.
This signal is output to the time measuring unit 65 as the measurement end signal h, and the time measuring unit 65 ends the time measurement. In this way, the predetermined time is subtracted from the time measurement section T2,
The time t2 during which the ultrasonic wave U propagates through the measured object A is measured.

[0005]

In order to improve the measurement accuracy in such a conventional ultrasonic measuring device, it is necessary to measure the propagation time of ultrasonic waves with high resolution. However, there is a limit to increase the time measurement resolution of the time measurement unit. Therefore, there is a method of extending the propagation time of ultrasonic waves to extend the propagation time and improve the resolution.
For example, in the case of a densitometer, the distance between the transducer and the reflector may be widened and the object to be measured may be filled between them.
However, this method cannot be applied to a device in which the device is large and the propagation distance is fixed in advance such as a bolt axial force meter.

Next, another method for improving the measurement accuracy of the conventional ultrasonic measuring device will be described. As shown in FIG. 5, reflectors 52 and 53 that reflect ultrasonic waves well on both sides of the object to be measured.
Set up. Then, since the ultrasonic wave reciprocates several times between the reflectors 52 and 53, the transducer 51 obtains a reflected waveform as shown in FIG. For example, if the time is measured with the wave of b in the figure, the time can be expanded to twice that of the wave of a, and thus the measurement resolution can be doubled.

However, this method also has the following problems. Since the reflected waves are attenuated in the measured object, the number of reflected waves that can be observed is limited. Therefore, the resolution improvement is limited to several times. Depending on the object to be measured, the reflected wave is greatly attenuated and it cannot be applied to such a thing. Depending on the object to be measured, the reflectors cannot be installed on both sides of the object, and it is not applicable to such objects.

[0008]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide an ultrasonic measuring method and apparatus which can improve the measuring accuracy and can be applied to any object to be measured.

[0009]

An ultrasonic measuring method according to claim 1 is a pulser which is activated by a predetermined transmission signal to output a transmission wave signal, and an output from the pulser is converted into an ultrasonic wave. A transducer for transmitting and outputting reflected ultrasonic waves from the inside of the measured body and a comparator for outputting the received signal when the received wave signal output from this transducer is a predetermined value or more is provided. In the ultrasonic measurement method for measuring the propagation time of the ultrasonic wave in the body to be measured based on the time difference between the reception signal output from the comparator and the transmission signal, the pulsar is a reception signal output from the comparator. The second and subsequent transmission signals are output at the timing of.

An ultrasonic measuring apparatus according to a second aspect of the present invention is a pulsar which is activated by a predetermined transmission signal to operate and outputs a transmission wave signal, and an output from the pulsar which is converted into an ultrasonic wave and propagated into a body to be measured. A transducer that outputs and receives reflected ultrasonic waves from the inside of the body to be measured, a comparator that outputs a reception signal when the reception wave signal output from this transducer is a predetermined value or more, and a reception output from this comparator In an ultrasonic measurement device including a signal and the transmission signal, and a time measuring unit that measures the propagation time of the ultrasonic wave in the measured body based on the time difference between the signals, and is activated by the transmission signal. A switching circuit for switching and connecting the output circuit section of the comparator to the input section of the pulser is provided, and while counting the output pulse of the comparator, The value, characterized in that provided a counter for controlling switching to the original normal connection state the switch circuit when matching the number of times set in advance.

An ultrasonic measuring device according to a third aspect is the ultrasonic measuring device according to the second aspect, wherein the switching circuit comprises:
The pulser comprises an input circuit unit equipped with one switching device and an output circuit unit of the comparator equipped with another switching device, and both switching devices operate with the transmission signal. It is characterized in that it is electrically connected to each other and is activated by the output signal from the counter to return to the normal connection state.

[0012]

When the pulser outputs a transmission wave signal by being energized by a predetermined transmission signal, the transducer outputs ultrasonic waves into the body to be measured and receives reflected ultrasonic waves from the body to be measured. When the received wave signal is a predetermined value or more, the comparator outputs the received signal. This reception signal becomes a transmission signal, and the above operation is repeated again. By repeating this operation for a predetermined number of times, the ultrasonic wave has propagated back and forth within the body to be measured a predetermined number of times.

[0013]

1 is a block diagram showing an embodiment of an ultrasonic measuring method and an apparatus thereof according to the present invention, and FIG. 2 is a time chart showing an embodiment of an ultrasonic measuring method and an apparatus thereof according to the present invention. is there. Hereinafter, a detailed description will be given with reference to these drawings. However, the same parts as those in FIG. 3 and FIG.

The ultrasonic measuring device is operated by being urged by the transmission signal d from the transmission signal generator 61 and outputs the transmission wave signal e, and the output from the pulsar 62 is converted into ultrasonic waves U to be received. A transducer 51 for transmitting and outputting to the measurement object A and receiving reflected ultrasonic waves from the inside of the measurement object A;
A comparator 64 that outputs a reception signal g when the reception wave signal f that is output from the transducer 51 is a predetermined value or more, and a reception signal g that is output from the comparator 64.
And a transmission signal d, and a time measuring unit 65 that measures the propagation time of the ultrasonic wave in the measured object A based on the time difference between the ultrasonic measurement device and the ultrasonic measurement device. A switching circuit 10 for switching and connecting the output circuit section of the comparator 64 to the input section of the pulsar 62 is provided to count the output pulse (received signal g) of the comparator 64, and the count value matches the preset number of times. In this case, a counter 13 is provided which controls switching of the switching circuit 10 to the original connection state.
The switching circuit 10 is composed of a switching device 11A equipped in the input circuit part of the pulsar 62 and a switching device 11B equipped in the output circuit part of the comparator 64, and both switching devices 11A and 11B transmit It is assumed that the signals are activated by the signal d to conduct each other, and are activated by the output signal h from the counter 13 to return to the normal connection state. In addition, the transducer 5 is provided before the comparator 64.
A wide band amplifier 63 for amplifying the received wave signal f output from 1 is provided.

Next, the operation of this ultrasonic measuring device will be described. When the transmission signal generator 61 outputs the measurement start signal c and the transmission signal d, the time measuring unit 65 starts time measurement, the counter 13 is reset, and the switch 1
1B switches from the contact 1b to the contact 0b.
The switching device 11A switches from the contact 0a to the contact 1a by the falling signal of 1B. At the same time, the transducer 51 outputs the ultrasonic wave U into the measured object A by the transmission wave signal e from the pulsar 62. The reception wave signal f from the transducer 51 is amplified by the wide band amplifier 63, and then the reception signal g is output from the comparator 64 if the voltage value is equal to or higher than a predetermined value. The reception signal g passes from the contact 0b to the contact 1a to become the transmission signal d (shown by the broken line 20 in FIG. 1), and the above operation is repeated again. On the other hand, the received signal g is also output to the counter 13. The counter 13 counts the received signals g, and when the count value reaches a preset number (twice in FIG. 2), the output signal h changes to the switching circuit 1.
Output to 0. Contact 0b changes to contact 1 due to output signal h
The contact 1a is switched to the contact b and the contact 0a is switched to the contact 0a. In this case, the reception signal g becomes the transmission signal d through the contact 0b or the like before the output signal h, and the above operation is repeated only once. Then, the next received signal g is the contact 1b.
Is output to the time measuring unit 65 as a measurement end signal i. That is, if the number of times the counter 13 is set is N times, it means that the ultrasonic wave U propagates back and forth in the object A to be measured N + 1 times, and the propagation time is expanded N + 1 times as compared with the conventional method. You will be able to measure.

In the time measuring section T1 by the time measuring unit 65, the time t1 during which the ultrasonic wave propagates through the object A to be measured.
In addition to × (N + 1), a signal delay time, for example, the time from the output of the comparator 64 to the output of the pulser 62 is included. Since these signal delay times are determined by the set number N of the counter 13, they can be easily calibrated by providing a reference device.

[0017]

According to the ultrasonic measuring method and the apparatus therefor of the present invention, when M is a desired number, the ultrasonic waves can propagate back and forth M times in the body to be measured without being attenuated. The resolution can be improved by M times by extending the propagation time by M times while keeping the time measurement resolution as it is. Further, since the influence of the attenuation of the reflected wave is small and the reflector is not necessary, the present invention can be applied to the object to be measured with the large attenuation of the reflected wave or the object to which the reflector cannot be installed.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention.

FIG. 2 is a time chart showing the operation of the embodiment of the present invention.

FIG. 3 is a block diagram showing a configuration of a conventional example.

FIG. 4 is a time chart showing an operation of a conventional example.

FIG. 5 is an explanatory diagram of a main part of a conventional example.

FIG. 6 is a waveform diagram of a conventional example.

[Explanation of symbols]

 10 ... Switching circuit 11A, 11B ... Switching device 13 ... Counter 62 ... Pulser 51 ... Transducer 64 ... Comparator 65 ... Time measurement unit

Claims (3)

[Claims] 1. A pulsar which is activated by a predetermined transmission signal and outputs a transmission wave signal, and an output from the pulsar which is converted into an ultrasonic wave to be propagated and outputted to the inside of the body to be measured and to be outputted from the inside of the body to be measured. A transducer that receives reflected ultrasonic waves, and a comparator that outputs a reception signal when the reception wave signal output from this transducer is equal to or greater than a predetermined value, and the reception signal output from this comparator and the transmission signal In the ultrasonic measurement method for measuring the propagation time of ultrasonic waves in the measurement target body based on the time difference, the pulsar outputs a transmission signal from the second time onward at the timing of the reception signal output from the comparator. And ultrasonic measurement method. 2. A pulsar which is activated by being energized by a predetermined transmission signal and outputs a transmission wave signal, and an output from this pulsar which is converted into an ultrasonic wave to be propagated and outputted to the inside of the measured body and at the same time from the inside of the measured body A transducer that receives reflected ultrasonic waves, a comparator that outputs a reception signal when the reception wave signal output from this transducer is a predetermined value or more, and a reception signal output from this comparator and the transmission signal are input. In an ultrasonic measurement device having a time measuring unit that measures the propagation time of the ultrasonic wave in the body to be measured based on the time difference, an output circuit unit of the comparator that is activated by the transmission signal is activated and the pulse circuit is used. Equipped with a switching circuit for switching and connecting to the input part of, the output pulse of the comparator is counted, and the count value is set to a preset number of times. Ultrasonic measuring apparatus according to claim was that the switching circuit provided with a counter for controlling switching to the original normal connection state when. 3. The switching circuit is configured by one switching device equipped in the input circuit part of the pulser and the other switching device equipped in the output circuit part of the comparator, and switching of both of them. 3. The ultrasonic measuring device according to claim 2, wherein the device operates with the transmission signal to conduct each other, and operates with the output signal from the counter to return to the normal connection state.