JPH0989846A - Method and apparatus for diagnosing peeling of bonded surface - Google Patents

Abstract

PROBLEM TO BE SOLVED: To diagnose delamination on the bonded face of an article, e.g. a rubber roller, composed of different materials bonded each other nondestructively at the time of periodic inspection or the production stage. SOLUTION: A pair of elastic wave signal transmitting section 2 and receiving section 3 are arranged for a rubber roller. An elastic wave is transmitted through the rubber roller and the transfer function is calculated at a signal processing section 6 based on a transmission signal generated from a signal generator 5 to the signal transmitting section 2 and a receiving signal detected at the receiving section 3. Based on the transfer function thus calculated, a delamination diagnostic section 7 diagnoses delamination on the bonding face between a metallic or inorganic material and an elastic organic material.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a peeling diagnosis method and a peeling diagnosis apparatus for a joint surface, and more particularly to a peeling diagnosis method and a peeling diagnosis apparatus for a joint surface of an article formed by joining different materials.

[0002]

2. Description of the Related Art A typical example of an article formed by joining different materials is a rubber roller used in various plants and mobile equipment. This type of rubber roller often rotates at a high speed and a high load. Therefore, if an abnormality occurs in the rubber roller for some reason, the quality of the product may be deteriorated, the line and equipment may be stopped, and a serious accident involving human body may occur. The types of abnormalities of the rubber roller include damage to the rubber surface portion, separation of the joint surface between the rubber portion forming the roller and the central member, and the like. In particular, it is difficult to find the peeling of the joint surface between the rubber portion and the central member, and once the peeling occurs, an abnormality develops in a short time. Therefore, it is desired to find it early.

FIG. 16 is a view showing the basic structure of a rubber roller formed by joining different materials. FIG.
In FIG. 6, 101 is a core part and 102 is a rubber part.

A rubber roller, which is a typical article formed by joining different materials, is made of an organic material having elasticity for the purpose of reducing vibration and noise accompanying rotation and protecting products. A rubber portion (which need not be rubber but may be a soft resin or the like, but will be referred to as a rubber portion here) 102 and a rubber portion for supporting the rubber portion 102 and transmitting rotation. The core portion 1 made of a material different from that of the portion 2, for example, metal, inorganic material, hard resin, or the like.
And 01. And the core part 101 and the rubber part 102 are joined at the boundary part.

Such rubber rollers can be roughly classified into two types according to their usage. One is a type in which the rubber roller itself moves together with the object for the purpose of smoothly moving the object while supporting the load of the object, and the number of rubber rollers used is relatively small. On the other hand, the rubber roller itself is of a type that does not move for the purpose of moving, shaping, cleaning, etc. of products, and the number of rubber rollers used is relatively large and the number thereof is small.

Conventionally, most of the peeling diagnosis of the bonding surface of this type of rubber roller has been performed manually by an inspector. For example, the escalator step roller peeling diagnosis is performed by a method in which an inspector sandwiches the rubber portion of the roller with pliers and twists it lightly to inspect whether or not the joint surface is peeled.

Further, as a conventional technique relating to an automated peeling diagnosis system, peeling diagnosis of a joint surface between a rubber portion of a rubber roller called a ringer roll used in a process for producing a thin plate and a central member is performed in an iron mill. The technology is, for example, “Plant Engineer (199
March, March issue) "and the like.

In this prior art, the vibration of the bearing portion is measured to make a diagnosis. The peak value of the vibration velocity obtained from the acceleration type vibration sensor attached to the bearing portion is constantly monitored and the peak value is not appropriate. An abnormal alarm is issued when the threshold value is exceeded. Then, when an abnormality alarm occurs, the type of abnormality such as roll peeling, unbalance, and deterioration of surface quality is determined by comparing the waveform pattern of the vibration velocity with the waveform pattern obtained for each abnormality type in advance. It is a thing.

[0009]

The above-mentioned conventional technique can judge whether or not the joining surface is peeled, but has a problem that the position and size of the peeling cannot be diagnosed with high accuracy. Have Further, the above-mentioned conventional technique has a problem that the number of rubber rollers to be diagnosed such as the step roller for the escalator is large, and it is impossible to monitor and diagnose the movement of the bearing and the rubber roller.

The object of the present invention is to solve the above-mentioned problems of the prior art, and even during the periodic inspection, even when the joint surface of an article composed of different materials such as a rubber roller is minutely peeled off,
It is an object of the present invention to provide a peeling diagnosis method and a peeling diagnosis device for a bonding surface, which enables nondestructive diagnosis and detection in a manufacturing stage or the like.

[0011]

According to the present invention, the above object is a diagnostic object for a debonding diagnostic method of a bonded surface for diagnosing debonding of a bonded surface of an article formed by bonding different materials. A pair of an elastic wave signal transmission unit and a signal reception unit is arranged on the surface of the article so that the elastic wave propagates through the joint surface of the article, and is detected from the transmission signal and the signal reception section sent to the signal transmission section. This is achieved by determining the transfer characteristic of the elastic wave propagating in the article using the received signal, and diagnosing the peeling of the joint surface from this transfer characteristic.

[0012] Further, the above object is to provide an article constituted by joining the different materials, a natural rubber having elasticity around a core portion, NBR (acrylonitrile butadiene rubber), SBR (styrene butadiene rubber), This is achieved by using a roller provided with an organic material such as synthetic rubber typified by urethane rubber and using a frequency band of 2 MHz or less as the elastic wave.

Further, the above-mentioned object is (a) a coherence function between transmitted and received signals as a transfer characteristic of an elastic wave to be measured,
It is achieved by using a spectral function such as a transfer function, (b) a power spectrum of a received signal, (c) a peak voltage of an output signal (using a single frequency as a transmitted signal), and the like.

When the elastic wave from the signal transmitting unit is transmitted to the roller, the elastic wave having a frequency of 2 MHz or less propagates in the roller, but the elastic wave having a frequency of 2 MHz or more is severely attenuated in the rubber portion of the roller, It cannot propagate through the rubber part of the roller. For this reason, it is difficult to diagnose the peeling of the rubber roller by the ultrasonic echo method using a relatively high frequency. Therefore, the present invention uses a frequency band of 2 MHz or less as the elastic wave.

Table 1 shows usable frequency bands of elastic waves for diagnosing separation of rollers using various rubbers.

[0016]

[Table 1]

According to the present invention, an elastic wave signal transmitting portion and a signal receiving portion are arranged for the rubber roller, and the elastic roller signal from the core portion of the rubber roller is detected based on the transmission signal sent to the signal transmitting portion and the reception signal detected by the signal receiving portion. Diagnose the peeling of the rubber part. The frequency band used as a transmission / reception signal is 2 MHz or less, as shown in Table 1. In this frequency band, the rubber part resonates and a standing wave of a certain frequency mode is generated in the rubber part. Elastic waves in the low-frequency band below the resonance frequency, which is the cut-off region of the resonance, or in the high-frequency band in which the elastic waves are strongly attenuated and the higher-order modes do not stand, cannot propagate through the long-distance rubber part. , Can be propagated between the signal transmitting unit and the signal receiving unit via the core of the rubber roller.

Therefore, by adjusting the positions of the signal transmitting unit and the signal receiving unit so that the separation unit is located in the propagation path of the elastic wave having the frequency band as described above, the transfer characteristic used for the separation diagnosis. Changes depending on the presence or absence of peeling. By measuring the change in the transfer characteristic, it becomes possible to diagnose peeling.

Further, the elastic wave has a characteristic that its directivity becomes better as its frequency becomes higher. For this reason, when the low frequency band is used, it is possible to detect only the presence or absence of peeling regardless of the positions of the signal transmitting unit and the signal receiving unit. By measuring the transfer characteristics when the attachment positions of the signal receiving unit and the signal receiving unit are changed, the position and size of the peeling can be diagnosed.

As the transfer characteristics of the elastic wave to be measured,
(A) a spectrum function such as a coherence function between transfer signals and a transfer function, (b) a power spectrum of a received signal,
(C) The peak voltage of the output signal (using a single frequency as the transmission signal) or the like can be used. These transfer characteristics show that when the propagation path and propagation medium of elastic waves change,
It changes a lot. Therefore, these transfer characteristics greatly change even if the propagation path of the elastic wave changes due to the separation and the change of the transmissibility. By utilizing this change, it is possible to diagnose the presence or absence and degree of peeling.

Further, by using the feature quantity of (a), it is possible to sensitively detect the transfer characteristic of the elastic wave even when the received signal has a lot of noise, and it becomes possible to diagnose peeling. Furthermore, by using the feature quantities of (b) and (c), it is possible to simplify the signal processing unit that extracts parameters and shorten the signal processing time.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a rubber roller separation diagnosing method and a diagnosing apparatus according to the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a block diagram showing a functional configuration of a separation diagnosis apparatus according to a first embodiment of the present invention, and FIG. 2 is a diagram showing a configuration of a hardware system of the separation diagnosis apparatus according to a first embodiment of the present invention. FIG. 3 is a diagram for explaining the diagnostic principle using the transfer function of the present invention. 1 and 2, 1 is a rubber roller, 2 is a signal transmitting section, 3 is a signal receiving section, 4 is a signal transmitting / receiving section mounting jig, 5 is a signal generator, 6 is a signal processing section, 7
Is a separation diagnosis unit, 61 is a preamplifier, 62 is a main amplifier, 63 is an FFT analyzer, and 71 is a computer.

In the peeling diagnostic apparatus according to the first embodiment of the present invention, a rubber roller is taken as an example of an article to be diagnosed which is formed by joining different materials, and a bonding surface of a rubber portion and a core portion of the rubber roller 1 is This is to diagnose peeling. As shown in FIG. 1, this peeling diagnostic apparatus includes a signal transmitting unit 2 and a signal transmitting unit 2 configured to apply an elastic wave such as a sound wave to the rubber roller 1, which is composed of a piezoelectric element or the like arranged in contact with the outer peripheral portion of the rubber roller 1. A signal receiving portion 3 arranged in contact with the rubber roller 1 at another position, and a signal transmitting / receiving portion mounting jig 4 for fixing the signal transmitting portion 2 and the signal receiving portion 3 to the rubber roller 1 and outputting a mounting position signal. A signal generator 5 for outputting a transmission signal to the signal transmission unit 2, and the transmission signal and signal reception unit 3
The signal processing unit 6 which receives the received signal detected from the signal transmission unit 2 and the signal receiving unit 3 and obtains the transfer characteristic of the rubber roller 1, and the transfer characteristic obtained by the signal processing unit 6 gives a peeling evaluation index. Peeling from the peeling evaluation index calculated, the peeling determination data obtained in advance and stored, or the peeling determination data obtained by measurement, and the transmitter / receiver mounting position signal input from the transmitter / receiver mounting jig 4 And a peeling diagnosis unit 7 for performing the diagnosis.

The transmitter / receiver mounting jig 4 is used for the signal transmitter 2
Also, the signal receiving unit 3 is fixed to the rubber roller 1, and a transmission / reception unit mounting position signal, which is a signal regarding a relative mounting position of the signal transmitting unit 2 and the signal receiving unit 3 with respect to the rubber roller 1, is output to the peeling diagnosis unit 7. Further, the relative mounting positions of the signal transmission unit 2 and the signal reception unit 3 with respect to the rubber roller 1 can be changed manually or automatically.

The signal generator 5 generates a random signal when a spectral function is used as a transfer characteristic for diagnosis, and a single frequency when a peak voltage of a received signal is used as a transfer characteristic for diagnosis. Generates a sine wave of.

The signal processing unit 6 takes in the transmission signal output from the signal generator 5 and the reception signal detected by the signal receiving unit 3, and calculates a transfer characteristic used for diagnosis.
The transfer characteristic to be calculated may be a spectrum function such as a coherence function or a transfer function, a power spectrum from a received signal, or simply a parameter such as a peak voltage of the received signal.

The peeling diagnosis unit 7 calculates a peeling evaluation index and a full-circumference peeling index from the transfer characteristics calculated by the signal processing unit 6,
Peeling judgment data obtained in advance and stored, or
Peeling is diagnosed from the peeling determination data obtained by measurement, the peeling evaluation index, the full-circumference peeling index, and the transmitter / receiver mounting position signal input from the signal transmitter / receiver mounting jig 4.

As shown in FIG. 2, the hardware of the first embodiment of the present invention uses a pair of signal transmission / reception units, and the transmission / reception unit mounting of the simplest mechanism for manually changing the mounting position of the signal transmission / reception unit. It is configured by using a jig.
In FIG. 2 showing the hardware configuration, a signal transmission unit 2 and a signal reception unit 3 are provided on a rubber roller 1 such as a step roller.
Are mounted by the signal transmitting / receiving unit mounting jig 4.

A random signal is input to the signal transmitting unit 2 by the signal generator 5, and the received signal from the signal receiving unit 3 is amplified by the preamplifier 61 and the main amplifier 62 and input to the FFT analyzer 63. The FFT analyzer 63 receives the random signal output from the signal generator 5 and the reception signal from the main amplifier 62, and is located between the transmission signal and the reception signal, that is, the signal transmission unit 2 and the signal reception unit 3 of the rubber roller 1. Calculate the transfer function between and.

The computer 71 stores in advance peeling determination data obtained from preliminary experiments, or FF
The transfer function calculated by the T analyzer 63 is taken in, and the transfer function separation evaluation index calculated by the FFT analyzer 63 is calculated by using one of a plurality of transfer functions from the entire circumference of the rubber roller 1 whose position has been changed as separation determination data. Then, the peeling determination data stored in advance is compared with the peeling evaluation index, and the peeling diagnosis is performed by referring to the mounting position signal from the signal transmitting / receiving mounting jig 4.

Next, the diagnostic principle using the transfer function of the present invention will be described with reference to FIG.

Now, a rubber roller 1 having a rubber portion 102 bonded to a core portion 101 similar to that described with reference to FIG.
However, it is assumed that the signal transmission unit 2 and the signal reception unit 3 are attached to the signal transmission / reception unit attachment jig 4 so as to face each other through the center line of the rubber roller 1.

In this case, the signal transmitter 2 to the signal receiver 3
Core portion 101 and rubber portion 102 on the propagation path of the elastic wave reaching
If there is peeling on the joint surface between the and, the attenuation of the propagating elastic wave increases. Therefore, assuming that the transfer function in the normal case where there is no peeling on the joint surface is as shown in FIG. 3A, when there is peeling on the joint surface, the transfer function is
The gain is lower than that in the normal case, and becomes as shown in FIG. Therefore, the peeling situation can be diagnosed by measuring the decrease in gain from the normal value of the transfer characteristic. Specifically, a value obtained by integrating the difference from the transfer function in a normal case in the frequency band in which the gain decreases in each frequency region, that is, the area of the shaded portion in FIG. To use.

In order to calculate this peeling evaluation index, a reference transfer function, that is, a transfer function in a normal state is required. In the present invention, the reference data is 1
Among the transfer functions obtained at a plurality of positions of one diagnosis target, the transfer function having the best transfer characteristic, that is, the transfer function having a high transfer gain is used as the reference data. Alternatively, as the reference data, a transfer function previously measured using a normal rubber roller is used as the reference data.

In the description of the embodiments of the present invention described later, the peeling evaluation index obtained by using the former reference data is set as the peeling evaluation index 1, and the peeling evaluation index obtained by using the latter reference data is taken as the peeling evaluation. It will be described as an index 2. Whichever index is used to diagnose peeling, an increase in the peeling evaluation index indicates that the gain of the transfer function is decreasing, that is, the degree of peeling is high. Therefore, by setting an appropriate judgment threshold value in the peeling evaluation index, the degree of peeling can be diagnosed.

FIG. 4 is a flow chart for explaining a procedure for calculating a peeling evaluation index according to the first embodiment of the present invention, and FIG. 5 is a flow chart for explaining a diagnosis procedure according to the first embodiment of the present invention. The calculation procedure and the diagnosis procedure of the peeling evaluation index (hereinafter referred to as peeling evaluation index 1) using the first method according to the first embodiment of the present invention will be described with reference to FIG.

(1) Peeling evaluation index 1 calculation procedure 1000
First, the signal transmission unit 2 and the signal reception unit 3 are attached to the rubber roller 1 by the signal transmission / reception unit attachment jig 4, and a random signal is input to the signal transmission unit 2 from the signal generator 5. The elastic wave from the signal transmitting unit 2 propagates through the rubber roller 1, is received by the signal receiving unit 3, is amplified by the preamplifier 61 and the main amplifier 62, and is captured by the FFT analyzer 63 (step 1001).

(2) The FFT analyzer 63 obtains the transfer function Hk (f) (k: measurement position, f: frequency) based on the transmission signal (random signal) and the reception signal from the signal generator 5 (step). 1002).

(3) The computer 71 adds the gain of the transfer function Hk (f) obtained by the FFT analyzer 63 for the band of 2 MHz or less. As a result, the added value Ik at the measurement point k is determined. This value corresponds to the lower area of the curve showing the transfer function in FIG. This added value Ik can be expressed by the equation 1 (step 1003).

[0041]

[Equation 1]

(4) Next, it is judged whether or not the measurement is completed at all the measurement positions. If the measurement is not completed, the mounting positions of the signal transmitting section 2 and the signal receiving section 3 are moved to the next measuring position. Then, the processing from step 1001 is repeated (steps 1004 and 1005).

(5) In step 1004, when it is determined that the measurement at all positions is completed, the added value Ik
The maximum value Im is determined as the full-circumferential peeling index Im. This Im can be expressed by equation 2 (step 1
006).

[0044]

[Equation 2]

(6) Next, the peeling evaluation index 1 at each measurement point k is calculated by calculating the difference between the total circumference separation index Im determined above and the added value Ik at each measurement point k.
Calculate (S1k). The peeling evaluation index 1 (S1k) can be expressed by Equation 3 (step 1007).

[0046]

(Equation 3)

(7) Steps 1001 to 100 described above
When the peeling evaluation index 1 (S1k) and the full-circumference peeling index Im are obtained by the peeling evaluation index calculation procedure 1000 according to 7, the diagnostic procedure shown in FIG. 5 using these is started. First, it is determined whether the full-circumferential peeling index Im is smaller than the full-circumferential peeling threshold It obtained by measuring in advance,
If it is smaller, it is determined to be peeled around the entire circumference and displayed (steps 2001 and 2002).

(8) In step 2001, when it is determined that the all-round peeling index is larger than the all-round peeling threshold It, the peeling diagnosis is performed using the peeling evaluation index 1 (S1k) at each measurement point k. . This diagnosis is based on the peeling evaluation index 1
This is performed by determining whether (S1k) exceeds a predetermined peeling threshold value S1t (step 2003).

(9) When it is determined in step 2003 that the peeling evaluation index 1 (S1k) exceeds the predetermined peeling threshold value S1t, peeling has occurred at the measurement position k. If so, the display is performed, and in the opposite case, the display is determined to be normal (steps 2004 and 2005).

(10) It is judged whether or not the judgments at all the measurement positions have been completed. If not, step 200
The processing from step 3 is repeatedly executed, and if the determination at the measurement position is completed, the processing ends (steps 2006 and 20).
07).

FIG. 6 is a flow chart for explaining another example of the procedure for calculating the peeling evaluation index according to the first embodiment of the present invention, and FIG. 7 is another example of the diagnostic procedure according to the first embodiment of the present invention. 6 is a flow chart, and is shown in FIGS.
With reference to, a peeling evaluation index using the second method according to the first embodiment of the present invention (hereinafter referred to as peeling evaluation index 2)
The calculation procedure and the diagnosis procedure of will be described.

(1) Peeling evaluation index 2 calculation procedure 3000
First, the signal transmission unit 2 and the signal reception unit 3 are attached to the rubber roller 1 by the signal transmission / reception unit attachment jig 4, and a random signal is input to the signal transmission unit 2 from the signal generator 5. The elastic wave from the signal transmitting unit 2 propagates through the rubber roller 1, is received by the signal receiving unit 3, is amplified by the preamplifier 61 and the main amplifier 62, and is captured by the FFT analyzer 63 (step 3001).

(2) The FFT analyzer 63, based on the transmission signal (random signal) and the reception signal from the signal generator 5, transfers the transfer function Hk (f) (k:
Measurement position, f: frequency) is calculated (step 300)
2).

(3) The computer 71 uses the transfer function H0 (f) in the normal part, which is obtained and stored in advance, as a reference value, and the transfer function Hk (obtained by the FFT analyzer 63 in the frequency band of 2 MHz or less. The absolute value of the deviation of the gain of f) from the reference value is added, and the added value is obtained as the peeling evaluation index S2k at the measurement position k. The peeling evaluation index S2k can be expressed by the equation 4 (step 3003).

[0055]

[Equation 4]

(4) Next, it is judged whether or not the measurement at all the measurement positions is completed, and if not completed, the mounting positions of the signal transmission unit 2 and the signal reception unit 3 are set to the next measurement position. After moving, the process from step 3001 is repeated (steps 3004 and 3005).

(5) When it is determined in step 3004 that the measurement at all positions is completed, the procedure 3000 for calculating the peeling evaluation index 2 is ended, and then the peeling evaluation index 2 is used in FIG. The diagnostic procedure shown is started. First, the peeling evaluation index 2 (S2k) at the measurement position k is the peeling threshold value S.
It is determined whether or not it exceeds 2t (step 4001).

(6) If it is determined in step 4001 that the peeling evaluation index 2 (S2k) exceeds the predetermined peeling threshold value S2t, peeling has occurred at the measurement position k. If it is determined to be normal, the display is performed, and in the opposite case, it is determined to be normal and the display is performed (steps 4002 and 4003).

(7) It is judged whether or not the judgments at all the measurement positions have been completed. If not, step 400
The process from 1 is repeatedly executed, and if the determination at the measurement position is completed, the process ends (steps 4004, 4040).
05).

The above-described first embodiment of the present invention is shown in FIG.
Although the rubber roller separation diagnosis as shown in FIG. 6 is performed, the case where the present invention is applied to the separation diagnosis of the step roller for the escalator will be described as a specific example of the rubber roller.

FIG. 8 is a diagram showing an example of the structure of a step roller,
FIG. 9 is a diagram for explaining the attachment positions of the signal transmission unit and the signal reception unit, and FIGS. 10 to 12 are diagrams for explaining the results of the peeling inspection.

As shown in FIG. 8, the step roller has a core portion 101 and a rubber portion 102 as described with reference to FIG.
The core portion 101 is made of a steel material having a ball bearing, and the rubber portion 102 around the core portion 102 is formed of
Is made of urethane rubber or nitrile rubber. In the example described below, the rubber portion 102 made of urethane rubber or nitrile rubber and the core portion 10 made of steel material.
Detachment of the boundary surface of No. 1 shall be diagnosed.

As shown in FIG. 9, the mounting positions of the signal transmitting unit 2 and the signal receiving unit 3 are positions where the signal transmitting unit 2 and the signal receiving unit 3 are diagonal (180 °), and 2 and the signal receiving unit 3 are mounted on the urethane rubber of the rubber unit 102 using the signal transmitting / receiving unit mounting jig 4.
A line connecting the center 8 of the peeling portion and the center 9 of the roller is used as a reference line 10, and an attachment position is represented by an angle formed by the reference line 10 and a straight line connecting the signal transmitting unit 2 and the signal receiving unit 3. To do.

Nitrile rubber is used for the rubber portion 102 of the step roller shown in FIG. 8 described above, and the result of transfer function measurement as a result of inspecting the step roller for peeling using the diagnostic apparatus according to the embodiment of the present invention is shown. It is shown in FIG. In FIG. 10, the signal transmitter 2 and the signal receiver 3
The mounting position of and is a position of 0 degree, that is, the case where the signal transmitting unit 2 is on the peeling center part.

As can be seen from FIG. 10, a frequency of 30k
At Hz-110 kHz and 170 kHz-1.0 MHz,
The gain of the transfer function is reduced when there is a large amount of peeling, compared with the case where it is normal. This phenomenon occurs because the propagation of elastic waves is disturbed by peeling, and elastic waves with a frequency of 110 kHz to 170 kHz that are not affected by the presence or absence of peeling receive the signal without passing through the steel part due to the resonance of nitrile rubber. Propagate to part 3. On the other hand, frequency 30
The elastic waves of kHz to 110 kHz and 170 kHz to 1.0 MHz do not propagate in the nitrile rubber but once propagate through the steel material portion to the signal receiving portion 3. Therefore, the frequency 30
Since the elastic waves of kHz to 110 kHz and 170 kHz to 1.0 MHz are blocked by the separation in the propagation path,
This leads to a decrease in gain in that frequency band.

In the embodiment of the present invention, 170 kHz to 1.0 MHz is used as the frequency band of the elastic wave when the peeling evaluation index is obtained based on the above result. This is because the elastic wave in this band has a large deviation in the transfer function between the normal portion and the peeled portion, and has higher directivity. Further, when obtaining the peeling evaluation index 2, the value of the transfer characteristic of a normal product is used as a reference value.

Next, the result of obtaining the peeling evaluation index of the entire circumference of the step roller having the peeling portion by the method described above is shown in FIG.
1 and FIG.

FIG. 11 shows the results of obtaining the peeling evaluation index 1 and the peeling evaluation index 2 by changing the pressing pressure of the signal transmitting unit 2 and the signal receiving unit 3 with respect to the step roller having the peeling unit. As can be seen from FIG. 11, when the pressing pressure is as small as 80 g weight, the peeling evaluation index 1 and the peeling evaluation index 2 both have increased index values at the peeling portion, and the peeling position can be located. In addition, the peeling evaluation index 1 has a larger difference in index value between the normal portion and the peeling portion than the peeling evaluation index 2, and the peeling position can be located with high accuracy.

Further, when the pressing pressure is increased to 800 g weight, the peeling evaluation index 2 shows almost no increase in the index value at the peeling portion and the diagnosis cannot be made, whereas the peeling evaluation index 1 shows that the pressing pressure is The index area increases as well as when it is small, and the separation can be diagnosed. The reason for this is that the peeling evaluation index 1 makes a relative evaluation for each lot. That is, the peeling evaluation index 1 is the individual difference between lots,
The peeling diagnosis can be performed without being affected by the change in the transmission characteristics due to the sensor pressing pressure.

On the other hand, in the peeling evaluation index 2, since the peeling determination data is prepared in advance, it is possible to calculate the index value every time the transfer characteristic is measured, and the sensor mounting method. By improving the above and improving the reproducibility of the data, it is possible to perform the delamination diagnosis by catching a minute change in the transfer characteristic with respect to the change in the frequency.

FIG. 12 shows the results of examining the relationship between the measurement position (angle) and the peeling evaluation index 1 for step rollers having different peeling degrees. Although FIG. 12 shows an example in which the degree of peeling is large and the degree of peeling is small, in the embodiment of the present invention, the peeling threshold is set to be careful, small peeling, medium peeling, and large peeling, respectively. For example, by using the evaluation indexes 600, 1000, 3000, and 4000 as the peeling determination data, the degree of peeling can be diagnosed.

FIGS. 13 and 14 are views for explaining the results of inspecting the peeling of the step roller using the urethane rubber for the rubber portion by using the diagnostic device according to the embodiment of the present invention. FIG. 13 shows the transfer function. FIG. 14 shows the measurement results and the relationship between the measurement position (angle) and the peeling evaluation index 1. However,
The mounting position of the signal transmitting unit 2 and the signal receiving unit 3 is a position of 0 degree, that is, the case where the signal transmitting unit 2 is on the peeling central portion.

As can be seen from FIG. 13, a frequency of 30 kHz
At 90 kHz and 200 kHz to 2.0 MHz, the gain of the transfer function is reduced in the case where there is peeling as compared with the case where it is normal. According to this result, in the embodiment of the present invention, when the peeling evaluation index is obtained based on the above result, the frequency band of the elastic wave is 200 kHz to 2.0 MHz.
Decided to use. The reason is the same as in the case of nitrile rubber. The relationship between the measurement position (angle) of the step roller having the peeling portion and the peeling evaluation index 1 is
As shown in FIG. 14, the peeling diagnosis can be performed for urethane rubber as in the case of nitrile rubber.

FIG. 15 is a diagram showing the configuration of the hardware system of the separation diagnosis apparatus according to the second embodiment of the present invention. In FIG. 15, 11 is a DSP, 12 is a DI / O board,
13 is an MPX, 14 is a D / A board, 15 is an amplifier, 1
Reference numeral 6 is an A / D board, 17 is a speaker, and other reference numerals are the same as those in FIG.

The second embodiment of the present invention shown in FIG.
It is possible to realize the downsizing of the peeling diagnostic device and the speedup of the peeling diagnosis, and a plurality of pairs of the signal transmitting units 2 and the signal receiving units 3 are attached to the step roller 1 to be used for the measurement. And the signal receiving unit 3 are changed to move the measurement position to speed up the diagnosis, and the signal generator,
The signal processing unit and the peeling diagnosis unit are realized by the same hardware system. The peeling diagnosis apparatus according to the second embodiment of the present invention shown in FIG.
In addition, three pairs of the signal transmitting unit 2 and the signal receiving unit 3 are mounted by the signal transmitting / receiving unit mounting jig 4.

In FIG. 15, a DSP (digital signal processor) 11 drives an MPX (multiplexer) 13 via a DI / O (digital input and output) 12, and a signal transmitter 2 and a signal receiver 3 are connected. Have selected a pair of. The transmission signal is generated by the DSP 11, converted into an analog signal by the D / A board 14, and given to the signal transmission unit 2 via the MPX 13.
Further, the received signal is received by the signal receiving unit 3 and the MP
A / D16 amplified by the amplifier 15 via X13
Converted to a digital signal by the board 16 and the DSP 11
Is taken into. Further, the DSP 11 performs the above-described signal processing based on the transmission signal and the reception signal to diagnose peeling and informs the peeling by the buzzer 17.

The second embodiment of the present invention described above is an example in which the present invention is applied to the rubber separation diagnosis of the escalator step roller, but the present invention can be modified as described below. Is.

(1) The transfer characteristic obtained from the transmitted / received signal is
It is not necessary to limit to the transfer function, and any physical quantity that can quantitatively capture the change in the transfer characteristic of the elastic wave due to separation can be used. For example, a coherence function, a peak voltage of a received signal, etc. can be used as other transfer characteristics.

(2) The transmission signal is not limited to a random wave,
It is also possible to use a sine wave or the like depending on how to select the transfer characteristic.

(3) Although the signal transmitter and the signal receiver are arranged at diagonal positions (180 degrees), it is not necessary to limit to this method, and the signal transmitter and the signal receiver may be arranged. ,
Any arrangement may be adopted as long as the peeling portion is located in the elastic wave propagation path.

(4) The mounting positions of the signal transmitting section and the signal receiving section may be moved by rotating the mounting jigs for the pair of signal transmitting sections and the signal receiving section, and a plurality of pairs of signal transmitting sections may be transmitted. It may be performed by changing the pair of the signal transmitting unit and the signal receiving unit to be used by using the unit and the signal receiving unit.

(5) The calculation of the transfer characteristic is not limited to the method of using a pair of transmission / reception signals, but it is also possible to use a plurality of signal receiving sections for one signal transmitting section. The diagnosis time can be shortened.

In the above-described embodiment of the present invention, the present invention has been described as diagnosing peeling from the core of the rubber roller.
INDUSTRIAL APPLICABILITY The present invention can be applied to articles of any shape configured by joining materials of different materials.

[0084]

As described above, according to the present invention, even minute peeling of the joint surface of an article constituted by joining different materials such as a rubber roller is non-destructive during the periodic inspection, the manufacturing stage, etc. Can be detected diagnostically.

[Brief description of drawings]

FIG. 1 is a block diagram showing a functional configuration of a separation diagnosis apparatus according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a configuration of a hardware system of the separation diagnosis apparatus according to the first embodiment of the present invention.

FIG. 3 is a diagram illustrating a diagnostic principle using a transfer function of the present invention.

FIG. 4 is a flowchart illustrating a procedure for calculating a peeling evaluation index according to the first embodiment of the present invention.

FIG. 5 is a flowchart illustrating a diagnostic procedure according to the first embodiment of the invention.

FIG. 6 is a flowchart illustrating another example of a procedure for calculating a peeling evaluation index according to the first embodiment of the present invention.

FIG. 7 is a flowchart illustrating another example of the diagnostic procedure according to the first embodiment of the invention.

FIG. 8 is a diagram showing a structural example of an escalator step roller which is a diagnosis target.

FIG. 9 is a diagram illustrating the mounting positions of the signal transmission unit and the signal reception unit when performing the peeling diagnosis of the step roller.

FIG. 10 is a diagram showing a transfer characteristic as a result of inspecting peeling of a nitrile rubber step roller.

FIG. 11 is a diagram illustrating the results of obtaining the peeling evaluation index 1 and the peeling evaluation index 2 when the pressing pressure of the signal transmitting / receiving unit is changed.

FIG. 12 shows step rollers having different peeling degrees.
It is a figure explaining the result of having investigated the relationship between a measurement position (angle) and exfoliation evaluation index 1.

FIG. 13 is a graph showing a transfer characteristic as a result of inspecting peeling of a urethane rubber step roller.

FIG. 14 is a diagram showing a relationship between a measurement position (angle) and a peeling evaluation index 1 for a urethane rubber step roller.

FIG. 15 is a diagram showing a configuration of a hardware system of a separation diagnosis apparatus according to a second embodiment of the present invention.

FIG. 16 is a diagram showing a basic structure of a rubber roller configured by joining different materials.

[Explanation of symbols]

 1 rubber roller 2 signal transmitter 3 signal receiver 4 signal transmitter / receiver mounting jig 5 signal generator 6 signal processor 7 peeling diagnosis unit 11 DSP 12 DI / O board 13 MPX 14 D / A board 15 amplifier 16 A / D board 17 speaker 61 preamplifier 62 main amplifier 63 FFT analyzer 71 computer

Claims (12)

[Claims] 1. In a method for diagnosing peeling of a joint surface of an article composed of different materials joined together, an elastic wave propagates through the joint surface of the article to be diagnosed. , Arranging a pair of an elastic wave signal transmission unit and a signal reception unit on the surface of the article, using the transmission signal to be sent to the signal transmission unit and the reception signal detected from the signal reception unit,
A method for diagnosing debonding of a joint surface, which comprises deriving a transfer characteristic of an elastic wave propagating in the article and diagnosing debonding of the joint surface based on the transfer characteristic. 2. The debonding diagnosis of the joint surface according to claim 1, wherein the article formed by joining the different materials is a roller provided with an organic material having elasticity around a core portion. Method. 3. The organic material is natural rubber, or
The method for diagnosing peeling of a joint surface according to claim 2, which is a synthetic rubber represented by NBR (acrylonitrile butadiene rubber), SBR (styrene butadiene rubber), urethane rubber and the like. 4. The frequency band having a frequency band of 2 MHz or less is used as the elastic wave.
The method for diagnosing peeling of a joint surface according to 2 or 3. 5. The method according to claim 2, 3 or 4, wherein the elastic wave signal transmitter and the plurality of signal receivers are arranged on the surface of the roller. 6. A transfer function as a transfer characteristic of an elastic wave by a transmission signal and a reception signal is obtained at a plurality of points of one article, and the gain of the obtained transfer function is added in the frequency band of the transmission signal, The maximum value among the addition values obtained at the measurement points is the full-scale peeling index, the amount of reduction from the full-scale peeling index of the added value is the peeling evaluation index, and from this peeling evaluation index and the full-scale peeling index, in advance, The method for diagnosing peeling of a joint surface according to any one of claims 1 to 5, wherein the peeling is diagnosed based on the obtained peeling determination data. 7. A transfer function as a transfer characteristic of an elastic wave by a transmission signal and a reception signal is obtained, and a transfer function in a normal part obtained in advance is used as a reference value, and a transfer function of the transfer function in a frequency band of the transmission signal is obtained. The absolute value of the deviation of the gain from the reference value is added, and the obtained added value is used as the peeling evaluation index,
The method for diagnosing peeling of a joint surface according to any one of claims 1 to 5, wherein peeling is diagnosed based on the peeling determination data obtained in advance from the peeling evaluation index. 8. A coherence function is used as a transfer characteristic, according to any one of claims 1 to 5.
The method for diagnosing peeling of a joint surface as described above. 9. A frequency band excluding a resonance frequency band of an organic material having elasticity is used as a frequency band of an elastic wave.
The method for diagnosing peeling of a joint surface as described above. 10. The peeling of the joint surface according to claim 2, wherein a pair of the elastic wave signal transmitting portion and the elastic wave receiving portion is arranged at a position where the rollers face each other. Diagnostic method. 11. A bonding surface peeling diagnostic device for diagnosing peeling of a bonding surface of an article composed of different materials bonded together, wherein an elastic wave propagates through the bonding surface of the article to be diagnosed. A signal transmitting unit and a signal receiving unit of the elastic wave arranged, a signal transmitting and receiving unit attaching jig for attaching the signal transmitting unit and the signal receiving unit to the article to be diagnosed, and a signal generator for generating a signal to be sent to the signal transmitting unit. The signal processing unit for obtaining the transmission characteristic of the elastic wave from the transmission signal and the reception signal, and calculating the peeling evaluation index from the transmission characteristic, by comparing the peeling determination data and the peeling evaluation index obtained in advance, A debonding diagnostic device for diagnosing debonding, comprising: a debonding diagnostic device for a bonding surface. 12. The article formed by joining different materials is a roller provided with an organic material having elasticity around a core portion, and the signal transmission / reception unit mounting jig includes the signal transmission unit and the signal transmission unit. The bonding surface according to claim 11, wherein a plurality of pairs of signal receiving portions are attached to the roller, and any pair can be selected from the plurality of pairs of the signal transmitting portion and the signal receiving portion. Peeling diagnostic device.