JP2008286622A - Ultrasonic measuring device and ultrasonic measuring method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To measure accurately in a short time, the speed of an ultrasonic wave propagating inside, even when a measuring object has a large size. <P>SOLUTION: This ultrasonic measuring device has an ultrasonic transmitter 10 for transmitting an ultrasonic wave into a measuring object P having a fixed thickness; and a plurality of ultrasonic receivers 20, 21, 22 arranged at fixed array intervals L, for receiving the ultrasonic wave propagating inside the measuring object P. The device also has a propagation time measuring means 3a for measuring a propagation time of the ultrasonic wave propagating inside the measuring object P based on a timing of the ultrasonic wave transmitted and received between the ultrasonic transmitter 10 and each ultrasonic receiver 20, 21, 22, and a propagation speed calculation means 32B for averaging and calculating the propagation speed of the ultrasonic wave propagating inside the measuring object P based on each propagation time and the array intervals L of each ultrasonic receiver 20, 21, 22. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an ultrasonic measurement apparatus and an ultrasonic measurement method for measuring the speed of ultrasonic waves propagating in a motor case of a rocket motor, for example.

Conventionally, what performs a nondestructive inspection of the motor case (wall) of a rocket motor using an ultrasonic wave is known, for example.
The nondestructive inspection using ultrasonic waves is based on the calculation of the velocity V (m / s) of ultrasonic waves propagating in the motor case, which is a measurement of the motor case measured in advance by a caliper gauge or the like. Based on the thickness of the part and the propagation time of the ultrasonic wave in the measurement part, the following formula is used.
V = (2T × 1000) / t
“T” is the propagation time (s) of the ultrasonic wave propagating in the motor case, and “T” is the thickness (mm) of the measurement site of the motor case.

  However, when the motor case is enlarged, a measurement site where a commercially available caliper gauge does not reach is generated. Furthermore, when the motor case is made of fiber reinforced plastic, the thickness of the measurement site changes greatly due to temperature change. In addition, there is a problem that an accurate propagation velocity cannot be measured.

On the other hand, there is an ultrasonic measurement device having a configuration disclosed in Patent Document 1 in an attempt to solve the above problems.
The ultrasonic measurement device disclosed in Patent Document 1 obtains reflected wave echo data by changing the intervals of a plurality of ultrasonic transducers little by little, and obtains while changing the bulk wave sound velocity as a parameter. The reflected echo data is subjected to a migration process so that the peak position of the reflected echo is in phase, and the bulk wave sound velocity value when the peak value of the reflected echo is maximum is used as the bulk wave sound velocity of the medium. .
JP 9-318607 A

However, the conventional ultrasonic measurement device disclosed in Patent Document 1 does not need to measure the thickness of the measurement part of the measurement object in advance, but in order to obtain reflected wave echo data, It is necessary to perform measurement while changing the distance between each other little by little, and it is troublesome to confirm and move the distance between the ultrasonic transducers and requires time.
Therefore, the present invention is intended to provide an ultrasonic measurement apparatus capable of accurately measuring the velocity of ultrasonic waves propagating through a large measurement object in a short time.

  The ultrasonic measurement apparatus according to claim 1 receives an ultrasonic wave transmitter that transmits ultrasonic waves into a measurement object having a certain thickness, and an ultrasonic wave that propagates through the measurement object; A plurality of ultrasonic receivers having a predetermined array interval, and based on the timing of ultrasonic waves transmitted and received between the ultrasonic transmitter and each ultrasonic receiver, Propagation time measuring means for measuring the propagation time of the ultrasonic wave propagating in the measurement object, and the propagation speed of the ultrasonic wave propagating in the measurement object based on the above-described propagation time and the arrangement interval of each ultrasonic wave receiver It is characterized by having a propagation velocity calculation means for calculating by averaging.

  An ultrasonic measurement apparatus according to a second aspect includes an ultrasonic transmitter disposed on one of the two surfaces forming the thickness of the measurement object according to the first aspect, and a plurality of ultrasonic receptions on the other. It is characterized by the arrangement of vessels.

  The ultrasonic measuring apparatus according to claim 3 is an ultrasonic transmitter and a plurality of ultrasonic receivers arranged on one or the other of the two surfaces forming the thickness of the measurement object according to claim 1. It is characterized by.

  The ultrasonic measurement apparatus according to claim 4 has a jig for holding the plurality of ultrasonic receivers according to any one of claims 1 to 3 at a predetermined arrangement interval. It is a feature.

  The ultrasonic measurement apparatus according to claim 5 includes a plurality of the ultrasonic transmitters according to any one of claims 1 to 4 arranged at a predetermined interval, and of the ultrasonic transmitters. , Characterized in that it has a transmitter switching means for alternatively and sequentially switching the ultrasonic transmitter to be driven.

  The ultrasonic measurement method according to claim 6, wherein an ultrasonic wave is transmitted from an ultrasonic transmitter into a measurement object having a certain thickness, and the ultrasonic waves propagating through the measurement object are arranged at a predetermined arrangement interval. The ultrasonic wave is received by a plurality of ultrasonic receivers, and the timing of the ultrasonic waves transmitted and received between the ultrasonic transmitter and each ultrasonic receiver is measured. Based on the above, the propagation time of the ultrasonic wave propagating in the measurement object is measured, and the propagation speed of the ultrasonic wave propagating in the measurement object is averaged based on the above propagation times and the arrangement intervals of the ultrasonic receivers. It is characterized by being calculated.

According to the first aspect of the present invention, the propagation times of the ultrasonic waves received by the plurality of ultrasonic receivers are measured, and based on the measured propagation times and the arrangement intervals of the ultrasonic receivers. Because the average propagation speed of the ultrasonic wave propagating through the measurement object having a certain thickness is calculated, the sound velocity of the ultrasonic wave propagating through the measurement object even if it is a large measurement object Can be measured accurately in a short time.
Further, the manufacturing cost can be reduced, and molding defects such as delamination can be found even when the measurement object is formed of, for example, fiber reinforced plastic.

In addition to the above-described effects obtained by the invention described in claim 1, the following effects can be obtained according to the invention described in each claim.
According to the second aspect of the present invention, the ultrasonic waves transmitted from the ultrasonic wave transmitter arranged on one surface forming the thickness propagate in the object to be measured and are arranged on the other surface. Since the wave is received by the wave receiver, the sound speed of the ultrasonic wave propagating through the measurement object can be accurately measured.

  According to the invention described in claim 3, the ultrasonic wave transmitted from the ultrasonic wave transmitter disposed on one surface forming the thickness propagates through the object to be measured and is reflected on the other side surface, and then is transmitted. Since it is received by a plurality of ultrasonic receivers arranged on the same surface as the detector, it is possible to accurately measure the speed of ultrasonic waves propagating in the measurement object only on one side of the measurement object.

  According to the fourth aspect of the present invention, each ultrasonic receiver can be set to a predetermined arrangement interval in a short time only by holding a plurality of ultrasonic receivers on the jig.

  According to the fifth aspect of the present invention, a plurality of ultrasonic transmitters are arranged at a predetermined interval, and among these ultrasonic transmitters, an ultrasonic transmitter to be driven is selected. Therefore, the sound velocity of the ultrasonic wave propagating through the measurement site of the measurement object can be averaged and measured more accurately.

  Hereinafter, an ultrasonic measurement apparatus of the present invention will be described with reference to the drawings. FIG. 1 is a schematic block diagram showing the overall configuration of the ultrasonic measurement apparatus according to the first embodiment.

  The ultrasonic measurement apparatus A according to the first embodiment measures the velocity of ultrasonic waves propagating in the measurement object P, and includes a single ultrasonic transmitter 10 and three ultrasonic receivers. 20, 21, 22, a relay box 30 to which the ultrasonic receivers 20, 21, 22 are connected, a pulser / receiver 31, and a controller 32.

  The measuring object P is a flat body such as a fiber reinforced plastic (FRP) having a certain thickness T, but may be bent.

The ultrasonic transmitter 10 is disposed in close contact with one surface P1 of both surfaces (upper and lower surfaces in the drawing) P1 and P2 forming the thickness of the measurement object P, and three ultrasonic receivers 20 and 21 are provided. , 22 are arranged in close contact with the other surface P2.
The relative positional relationship between the ultrasonic transmitter 10 and the ultrasonic receivers 20, 21, and 22 is that the ultrasonic waves transmitted from the ultrasonic transmitter 10 are converted into the ultrasonic receivers 20, 21, It suffices if they are opposed to each other so that they can be received at 22.
In FIG. 1, the ultrasonic wave transmitter 10 is arranged on one surface P1 of the measurement object P, and the three ultrasonic wave receivers 20, 21, 22 are arranged on the other surface P2. Of course, it may be arranged on the opposite side.

  The three ultrasonic receivers 20, 21, and 22 are set to a predetermined arrangement interval L with respect to each other. That is, in the present embodiment, an example with equal intervals is shown, but different arrangement intervals may be used.

  The relay box 30 houses relays (not shown) that turn on / off the ultrasonic transmitter 10 and the ultrasonic receivers 20, 21, 22 in accordance with a control signal sent from a controller 32 to be described later. It is.

  The pulser / receiver 31 has both a function as a pulser that outputs a drive signal to the ultrasonic transmitter 10 and a function as a receiver that processes reception signals input from the ultrasonic receivers 20, 21, and 22. Is.

The controller 32 is a CPU that serves as a control center for the entire apparatus A, a required program, and a memory that stores a predetermined arrangement interval L between the above-described ultrasonic receivers 20, 21, and 22 (both not shown). The following functions are realized by executing the required program.
(1) Propagation time ta of the ultrasonic wave propagating in the measurement object P based on the timing of the ultrasonic wave transmitted / received between the ultrasonic wave transmitter 10 and each of the ultrasonic wave receivers 20, 21, 22 , Tb, tc (propagation time measuring means 32A).
Specifically, the propagation times ta, tb, and tc of the ultrasonic waves that propagate through the measurement object P are measured based on the ultrasonic pulses that are transmitted and received.
“Ta” is the propagation time of the ultrasonic wave received by the ultrasonic receiver 20, “tb” is the propagation time of the ultrasonic wave received by the ultrasonic wave receiver 21, and “tc” is the ultrasonic wave reception time. This is the propagation time of the ultrasonic wave received by the waver 22.

(2) Based on each propagation time ta, tb, tc and the arrangement interval L of the ultrasonic receivers 20, 21, 22, the propagation velocity V (m / s) of the ultrasonic wave propagating in the measurement object P A function of calculating by averaging (propagation speed calculating means 32B).
The ultrasonic wave propagation velocity V (m / s) can be calculated by averaging the following equation.

The ultrasonic measurement method using the ultrasonic measurement apparatus A having the above-described configuration is as follows.
Based on the timing of the ultrasonic waves transmitted and received between the ultrasonic transmitter 10 and each of the ultrasonic receivers 20, 21 and 22, the propagation time of the ultrasonic waves propagating in the measurement object P is measured. Based on the propagation times and the arrangement intervals of the ultrasonic receivers 20, 21, and 22, the propagation speed of the ultrasonic waves propagating in the measurement object P is averaged and calculated.
Specifically, when the ultrasonic pulse transmitted from the ultrasonic transmitter 10 is received by the ultrasonic receivers 20, 21, 22, the corresponding received signals are relay box 30, pulser / receiver 31. To the controller 32.

  In the controller 32, the propagation time ta, based on the timing of the ultrasonic pulse transmitted / received between the ultrasonic transmitter 10 and each ultrasonic receiver 20, 21, 22, and thus also the corresponding transmission / reception signal. While measuring tb and tc, the propagation speed V (m / s) of the ultrasonic wave is determined based on the propagation time ta, tb and tc and the arrangement interval L of the ultrasonic receivers 20, 21 and 22. The average is calculated as follows.

  FIG. 2 is a schematic block diagram showing the overall configuration of the ultrasonic measurement apparatus according to the second embodiment of the present invention. In addition, about the thing equivalent to what was demonstrated in FIG. 1, the same code | symbol is attached | subjected to them, description is abbreviate | omitted, and a difference is demonstrated in detail here.

The ultrasonic measurement apparatus B according to the second embodiment is configured by disposing the ultrasonic transmitter 10 and the ultrasonic receivers 20, 21, and 22 differently from those of the above-described embodiment. As shown in FIG. 2, the ultrasonic transmitter 10 and the ultrasonic receivers 20, 21, and 22 are arranged in parallel in close contact with one side surface (upper surface) P1 of the measurement site P.
In this configuration, the ultrasonic pulse transmitted from the ultrasonic transmitter 10 is reflected by the other side surface P2, and the reflected pulse is received by the ultrasonic receivers 20, 21, and 22.
When the reflected pulse is received by the ultrasonic receivers 20, 21, and 22, the corresponding received signal is input to the controller 32 via the relay box 30 and the pulser / receiver 31.
In the controller 32, the propagation time ta, based on the timing of the ultrasonic pulse transmitted / received between the ultrasonic transmitter 10 and each ultrasonic receiver 20, 21, 22, and also the corresponding transmission / reception signal. While measuring tb and tc, the ultrasonic wave propagation speed is averaged and calculated as described above based on the mutual arrangement interval L of the ultrasonic receivers 20, 21 and 22 stored in the memory.

  FIG. 3 is a schematic block diagram showing the overall configuration of the ultrasonic measurement apparatus according to the third embodiment of the present invention, and FIG. 4 is an exploded perspective view showing an example of a jig. Also in the present embodiment, the same components as those described in FIG. 1 are denoted by the same reference numerals and the description thereof is omitted, and differences will be described in detail here.

  The ultrasonic measurement apparatus C according to the third embodiment of the present invention has a predetermined arrangement interval L by three ultrasonic transmitters 10A, 10B, 10C and a jig 45 held at a fixed arrangement interval by the jig 40. The three ultrasonic receivers 20, 21, and 22 that are held, a relay box 30 that connects these ultrasonic receivers 20, 21, and 22, a pulsar receiver 31, and a controller 32 are configured.

As shown in FIG. 4, the jig 45 has three holding holes 42 for holding the ultrasonic receivers 20, 21, 22 formed in the arrangement interval L in the main body 41 formed in a rectangular parallelepiped shape. Therefore, the interval L can be easily aligned only by inserting the ultrasonic receivers 20, 21, 22 into the holding holes 42.
In addition, since the jig 40 for holding the ultrasonic transmitters 10A, 10B, and 10C has the same configuration as the jig 45, detailed description thereof is omitted. In addition, although the arrangement intervals of the ultrasonic receivers 20, 21, and 22 and the ultrasonic transmitters 10A, 10B, and 10C are the same value in the present embodiment, it is of course possible to have different values. It is.

  The controller 32 stores a CPU that is the control center of the entire apparatus C, a required program, and the arrangement intervals L of the ultrasonic receivers 20, 21, 22 and the ultrasonic transmitters 10A, 10B, 10C. In addition to the functions as the propagation time measuring means 32A and the propagation speed calculating means 32B, the following functions are realized by executing a required program. ing.

(3) A function of alternately switching the ultrasonic transmitters 10A, 10B, and 10C to be driven (transmitter switching means 32C).
In the present embodiment, the ultrasonic transmitters 10A, 10B, and 10C are automatically switched at regular time intervals. However, they may be switched at different time intervals, or may be switched manually. May be.

The operation of the ultrasonic measurement apparatus C having the above configuration is as follows.
First, when the ultrasonic pulse transmitted from the ultrasonic transmitter 10 </ b> A is received by the ultrasonic receivers 20, 21, and 22, the corresponding received signals are transmitted via the relay box 30 and the pulser / receiver 31. Input to the controller 32.
The controller 32 first measures propagation times ta, tb, and tc corresponding to the ultrasonic transmitter 10A.

After measuring the propagation times ta, tb, and tc, in other words, after a certain time has elapsed, the ultrasonic transmitter 10A is switched to the ultrasonic transmitter 10B.
When the ultrasonic pulse transmitted from the ultrasonic transmitter 10B is received by the ultrasonic receivers 20, 21, and 22, the corresponding received signals are transmitted to the controller via the relay box 30 and the pulser / receiver 31. 32.
The controller 32 measures the propagation times ta ′, tb ′, tc ′ corresponding to the ultrasonic transmitter 10B.

Then, after a certain time has passed, the ultrasonic wave transmitter 10B is switched to the ultrasonic wave transmitter 10C, and the ultrasonic pulse transmitted from the ultrasonic wave transmitter 10C is converted into the ultrasonic wave receivers 20, 21,. When the signal is received at 22, the corresponding received signal is input to the controller 32 via the relay box 30 and the pulser / receiver 31 in the same manner as described above, and the propagation time ta ″ corresponding to the ultrasonic transmitter 10 </ b> C. , Tb ″, tc ″.
Based on the measured propagation times ta, tb, tc, ta ′, tb ′, tc ′, ta ″, tb ″, tc ″ and the arrangement interval L of the ultrasonic receivers 20, 21, 22, Similarly, the propagation velocity V (m / s) of the ultrasonic wave propagating in the measurement object P is averaged and calculated, whereby a more accurate ultrasonic propagation velocity can be calculated.

The present invention is not limited to the above-described embodiment, and can be modified as follows.
In each of the above-described embodiments, an example in which three ultrasonic receivers 20, 21, and 22 are provided has been described. However, a configuration in which two or four or more ultrasonic receivers are provided may be employed. Also in this case, the ultrasonic wave propagation velocity is averaged and calculated by the same method as that used when the ultrasonic wave propagation velocity is averaged and calculated using the three ultrasonic receivers 20, 21, and 22. be able to.

  In each of the above-described embodiments, the arrangement interval of the ultrasonic receivers 20, 21, and 22 is set to a constant value. This is because the ultrasonic wave propagation velocity V (m / m) in the propagation velocity calculation means 32B is set. This is to facilitate the calculation of s), and therefore, the interval between them may be a different value.

In each of the above-described embodiments, the thickness calculating unit 32D (see FIG. 3) that calculates the thickness of the measurement object P may be provided based on the ultrasonic wave propagation velocity calculated by the propagation velocity calculating unit 32B.
Specifically, if the propagation velocity V is obtained, the thickness T of the measurement object P can be calculated by T = Vt / 2 in the case of a reflected wave, for example.

1 is a schematic block diagram showing an overall configuration of an ultrasonic measurement apparatus according to a first embodiment of the present invention. It is a schematic block diagram which shows the whole structure of the ultrasonic measuring device which concerns on 1st embodiment of this invention containing the ultrasonic wave transmitter and ultrasonic wave receiver which were made into the other example of arrangement | positioning. It is a schematic block diagram which shows the whole structure of the ultrasonic measuring device which concerns on 2nd embodiment of this invention. It is a disassembled perspective view which shows an example of a jig.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Ultrasonic transmitter 10A, 10B, 10C Ultrasonic transmitter 20, 21, 22 Ultrasonic receiver 32A Propagation time measurement means 32B Propagation speed calculation means 40, 45 Jig P Measurement object

Claims (6)

An ultrasonic transmitter that transmits ultrasonic waves into a measurement object having a certain thickness, and a plurality of ultrasonic waves that receive ultrasonic waves propagating through the measurement object and have predetermined array intervals. An ultrasonic measuring device comprising:
Propagation time measuring means for measuring the propagation time of the ultrasonic wave propagating in the measurement object based on the timing of the ultrasonic wave transmitted and received between the ultrasonic wave transmitter and each ultrasonic wave receiver,
Propagation speed calculating means for averaging and calculating the propagation speed of the ultrasonic waves propagating in the measurement object based on the propagation times and the arrangement intervals of the ultrasonic receivers. apparatus.   2. The ultrasonic measurement according to claim 1, wherein an ultrasonic transmitter is arranged on one of the two surfaces forming the thickness of the measurement object, and a plurality of ultrasonic receivers are arranged on the other surface. apparatus.   2. The ultrasonic measurement apparatus according to claim 1, wherein an ultrasonic transmitter and a plurality of ultrasonic receivers are arranged on one or the other of the two surfaces forming the thickness of the measurement object.   The ultrasonic measurement apparatus according to claim 1, further comprising a jig for holding a plurality of ultrasonic receivers at a predetermined arrangement interval. A plurality of ultrasonic transmitters are arranged at predetermined intervals,
The ultrasonic wave according to any one of claims 1 to 4, further comprising: a transmitter switching unit that sequentially and sequentially switches a driving ultrasonic transmitter among the ultrasonic transmitters. measuring device. Ultrasonic waves are transmitted from an ultrasonic transmitter into a measurement object having a certain thickness, and the ultrasonic waves propagating through the measurement object are received by a plurality of ultrasonic receivers with a predetermined array interval. An ultrasonic measurement method for measuring ultrasonic waves by
Based on the timing of the ultrasonic wave transmitted and received between the ultrasonic wave transmitter and each ultrasonic wave receiver, the propagation time of the ultrasonic wave propagating in the measurement object is measured,
An ultrasonic measurement method characterized by averaging and calculating the propagation velocity of ultrasonic waves propagating in the measurement object based on the propagation times and the arrangement intervals of the ultrasonic receivers.

Images