JP2734282B2 - Percussion equipment for building finishing materials - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention hits an outer wall tile of a building with a hammer or the like, and judges the adhesion state of the tile (whether or not there is peeling) from the sound of the hit at that time. The present invention relates to a percussion device for building finishing materials that automates and mechanizes work.

[0002]

2. Description of the Related Art In general, percussion work for inspecting a wall for peeling of a tile is performed by an inspector sensuously by hand. Skilled inspectors can perform extremely reliable percussion, but technical development is underway to automate such accurate percussion using a so-called inspection robot.

This kind of percussion device is a hammer-shaped device that locally strikes a wall or the like of a building to be inspected with a hammer driven by an appropriate actuator, and a microphone that collects a striking sound generated by the impact. When,
It basically comprises signal processing means for analyzing the vibration waveform of the striking sound obtained by the microphone.

In the apparatus disclosed in Japanese Patent Publication No. 2-54903, the frequency spectrum of a striking sound obtained from a sound wall having a good adhesion state of a tile is set as a reference, and its reference characteristics and other parts are set. Attempts are made to detect the peeling portion of the tile by comparing with the spectral characteristics of the striking sound obtained in (1). In the technique of Japanese Patent Application Laid-Open No. 63-168555, attention is paid to the damping characteristics of the striking sound, and the damping characteristics obtained from a healthy part without peeling are used as a reference. In comparison, we are trying to detect the peeled part.

[0005]

Both the method of making a judgment using the frequency spectrum characteristic of a striking sound as an index and the method of making a judgment using the attenuation characteristic of a striking sound as an index are performed by a skilled inspector with comprehensive hearing. There is a problem that a highly reliable inspection cannot be performed. What is particularly problematic is that in each of the two conventional methods, the frequency spectrum characteristic or attenuation characteristic obtained from the sound of a sound wall without separation is set as reference data, and it is compared with data obtained from other parts. However, it is very difficult to always compare and determine the sampling conditions of the reference data and the sampling conditions of the actual test data while always making them equal. For example, the striking sound is considerably different between when the center portion of the tile is struck and when the edge portion is struck, and the striking sound changes when the hammer-like striking is slightly different. It is very difficult to make the comparison conditions between the reference data obtained in the healthy part and the actual test data collected in many parts equivalent, without being affected by such fluctuation factors. Also, depending on the inspection target,
Although there may be a large difference in the frequency spectrum characteristics or attenuation characteristics of the impact sound between a healthy part and a peeled part, there are many cases where only subtle characteristics can be obtained, so that a highly reliable inspection can be realized. Did not.

SUMMARY OF THE INVENTION The present invention has been made in consideration of the above-mentioned conventional problems, and has as its object to analyze the vibration waveform of a striking sound collected by a microphone or the like to determine the quality of the bonded state of the finishing material. To increase the reliability of

[0007]

Therefore, in the percussion apparatus of the present invention, a percussion means for locally hitting a wall or the like of a building, an electroacoustic conversion means for detecting a vibration waveform of a percussion sound generated by the percussion, Signal processing means for obtaining a crest factor of the vibration waveform of the impact sound obtained by the electroacoustic conversion means, and determining whether the bonding state of the finishing material at the impact site is good or bad using the obtained crest factor as an index. .

[0008]

As is well known, the crest factor is a value obtained by dividing the maximum value of the peak of the vibration waveform by the effective value, and represents the sharpness of the waveform.
The peak value of the sine wave is 1.414 (route 2), the peak value of the triangular wave is 1.732 (route 3), and the peak value of the AC square wave is 1. The peak value becomes larger as the impulse-like waveform becomes sharper.

The inventors of the present invention have conducted tests at various sites, and as a result, the peak value of the vibration waveform of the impact sound generated from the sound wall is as large as about 2.5 or more. It was found that the peak value of the vibration waveform was as small as about 2 or less. In particular, regardless of the type of wall surface finishing material, there is a clear difference in the crest factor of the impact sound between the healthy part and the defective part. Instead, it was found that it was possible to discriminate between a healthy part and a defective part from the absolute value of the crest factor.

[0010]

FIG. 1 shows a schematic configuration of a percussion apparatus according to an embodiment of the present invention. The striking device 1 drives the hammer 2 with an actuator such as a motor or a hydraulic cylinder,
The tile wall 3 is hit locally with almost constant strength. The striking sound generated by the striking is collected by the microphone 4. The output of the microphone 4 is amplified by the preamplifier 5,
It is input to a peak hold circuit 6 and an effective value measurement circuit 7. The peak hold circuit 6 detects the peak value of the wave height of the striking sound waveform that attenuates like an impulse response. The effective value measuring circuit 7 calculates the effective value of the waveform until the impact sound waveform attenuates to a predetermined level. Division circuit 8
Then, the crest factor is calculated by dividing the peak value of the peak from the peak hold circuit 6 by the effective value from the effective value measuring circuit 7. The judging circuit 9 judges the quality of the adhesion state of the tile at the hit site using the crest factor calculated by the dividing circuit 8 as an index. The timing controller 10 controls the whole of the above elements synchronously.

In this embodiment, the same portion of the tile wall 3 is hit a plurality of times by the hitting device 1, and the judgment circuit 9 calculates the average value of the crest factors of the hitting sound measured at each hitting. Is 2.5 or more, it is determined to be healthy, and when it is 2 or less, it is determined to be defective. The middle part is determined to be a place requiring attention.

FIG. 2 shows a waveform of a hitting sound actually obtained from a tile wall surface of a certain building. Here group a ~
e is divided into five groups in which the percussion sounds are classified into five groups by percussion performed by a skilled inspector. As shown in this figure, the attenuation characteristics of the striking sound of each group are different, and the spectral characteristics are also different although not shown. However, it was difficult to obtain an effective and reliable index for judging the quality of the tile wall from these differences.
This is as described above.

In the apparatus of the present invention, the quality of the adhesion state of the tile wall surface is determined using the crest factor of the vibration waveform of the impact sound as an index. The crest factors of the striking sound waveforms of the five groups are shown in Table 1 below.

[0014]

[Table 1] As can be seen from the test results, the crest factor of the group a where the adhesion state of the tile is sound is as large as 2.1 or more, and the crest factors of the groups c, d and e where clear peeling is observed are 1.0.
It was as small as 9 or less. As described above, the crest factor is a very effective and highly reliable index for determining the adhesion state of the tile wall surface.

[0015] Table 2 shows the impact sounds measured on the simulated tile wall for test classified into eight groups, and the measured values of the crest factor of the impact sound waveform of each group are shown. This grouping is based on the consultation of a skilled inspector.

[0016]

[Table 2] From this test result, the crest factor of the impact sound in the healthy part is large,
It can be seen that the impact sound height ratio of the defective portion is small.

In addition, while the crest factor of the impact sound measured in a healthy state was 2.8 for the same tile on the wall surface of the tile, the tile was subjected to strong impact six times and peeled off. The crest factor of the impact sound measured in that state was 2.4, and the crest factor of the impact sound was 2.1 in a state where the impact was applied to increase the separation. From this test result, it was confirmed that the crest factor was an effective index for determining the state of the wall surface.

In the above embodiment, the crest factor of the striking sound is absolutely evaluated to determine the quality of the bonding state of the tiles. However, the present invention is not limited to this, and the crest factor of the striking sound obtained from the sound part is not limited to this. The determination may be made by a relative comparison with. Even in the case of relative comparison, the crest factor of the impact sound varies very little depending on how the impact is applied and the impact position on the tile, so the reliability is greatly improved compared to the relative comparison using the frequency spectrum characteristics and the attenuation characteristics as indices. be able to.

[0019]

As described in detail above, the percussion apparatus for a building finishing material according to the present invention obtains the crest factor of the vibration waveform of the impact sound, and uses the crest factor as an index to determine the bonding state of the finishing material at the impact site. The correlation that the crest factor is large in a healthy part and the crest factor is small in a defective part, even if the method of hitting or the position of hitting on the finishing material fluctuates, is almost changed. Without this, it is possible to inspect the peeled portion of the tile and the like with very high accuracy based on this.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a percussion device according to an embodiment of the present invention.

FIG. 2 is a vibration waveform diagram of an impact sound actually measured on a certain tile wall surface.

[Explanation of symbols]

 2 hammer 4 microphone

Continuation of the front page (56) References JP-A-63-168555 (JP, A) JP-A-57-173727 (JP, A) JP-A-60-260852 (JP, A) JP 2-54903 (JP) , B2)

Claims (1)

(57) [Claims] 1. A striking means for locally striking a wall or the like of a building, an electroacoustic converting means for detecting a vibration waveform of a striking sound generated by the striking, and the striking sound obtained by the electroacoustic converting means. And a signal processing means for obtaining a crest factor of the vibration waveform of (1), wherein the quality of the bonding state of the finishing material at the impact site is determined using the obtained crest factor as an index.