Quality evaluation method and quality evaluation apparatus

Abstract

The invention provides a quality evaluation method and a quality evaluation apparatus. Quality of industrial products is evaluated by evaluating non-stationary operation sound, which is a kind of operation sound, from an aspect of tone, using closely simulated evaluation levels of evaluation of non-stationary sound by used of a human sense of hearing. An operation sound of a conforming product sample is converted into sound waveform data by a sound collecting unit, and the sound waveform data is input into a computer via an A-D converter, and then converted into psychoacoustic parameters. Data of pseudo conforming products is additionally obtained from the psychoacoustic parameters of a plurality of conforming product samples by making use of deviation in the data of the conforming product samples. Threshold data is obtained using thresholds and masking data for evaluation calculated from psychoacoustic parameters of data of the conforming product samples and the pseudo conforming products by a statistical technique. An operation sound of a subject workpiece is converted into sound waveform data by the sound collecting unit, and the sound waveform data is input into the computer via the A-D converter, and then converted into psychoacoustic parameters. Each of the psychoacoustic parameters is compared with the corresponding one of the previously obtained threshold, and thereby the operation sound is evaluated.

Description

technical field [0001] The present invention relates to a quality inspection method of industrial products (such as motors, compressors, inverters, or products with built-in these, products with mechanical action mechanisms such as gears, cams, and sliders) accompanied by sound generation during operation. Background technique [0002] Except for some, almost all industrial products are more or less accompanied by action sounds when they are in action. This operating sound is emitted from power components such as motors, functional components such as compressors, electrical components such as inverters, and mechanical operating mechanisms such as gears, cams, and sliders. In a mass production process of an industrial product, product inspection using the operation sound is performed during or after product assembly. [0003] There are stable sounds and unsteady sounds as operating sounds emitted by industrial products. For example, in a motor, a compressor, etc. as equipme...

AI Technical Summary

Problems solved by technology

However, sometimes even if the sound pressure level is below the predetermined value, it may be considered as unacceptable due to the sound quality, and it is difficult to effectively judge the quality of industrial products only by the sound pressure level.

Images