Abstract: A metal surface inspection device for metal rings of a Continuously Variable Transmission (CVT) V-belt which does not perform excessive detection of mackerel skins as a detrimental manufacturing flaw. This task is achieved by providing an “integral value calculation portion” for calculating an integral value of a difference value and a “difference value correction portion” for correcting the difference value in a decreasing direction as the integral value increases. When mackerel skins contained on an inspectable surface are detected the output (integral value of the difference value) of the integral value calculation portion increases. Accordingly, the difference value is corrected in a decreasing direction which enables the operation to control the signal of the mackerel skin portions and threshold values are not exceeded which prevents excessive detection.

Abstract: An inspection device for metal rings of a Continuously Variable Transmission (CVT) V-belt which does not perform excessive detection of gloss marks as a detrimental manufacturing flaw configured with a first low-pass cutting portion for cutting out a predetermined low-frequency component contained in an electrical signal outputted from a first light detector or an electrical signal correlated to its electrical signal and a second low-pass cutting portion for cutting out a predetermined low-frequency component contained in an electrical signal outputted from a second light detector or an electrical signal correlated to its electrical signal, which precede a difference value calculation portion. The difference value calculation portion calculates a difference value between an electrical signal which passes through the first low-pass cutting portion and an electrical signal which passes through the second low-pass cutting portion.

Abstract: A metal surface inspection device which does not perform excessive detection of a harmless flaw, for example, a gloss mark. This task is achieved by providing a first discrimination portion which compares a difference value and a predetermined threshold value for discriminating the presence of a defect on an inspectable surface. This discriminated result is “provisional” and a final discrimination result is obtained by the operation of a second discrimination portion. Here, among the discriminated results of the first discrimination portion, the discrimination duration time corresponding to a harmful flaw is shorter and to the contrary the discrimination duration time corresponding to a harmless flaw is longer. Consequently, the difference between a harmful flaw and a harmless flaw are distinguishable by adjusting a discrimination reference value in the second discrimination portion.

Abstract: An inspection device for metal rings of a Continuously Variable Transmission (CVT) V-belt which does not perform excessive detection of gloss marks as a detrimental manufacturing flaw configured with a first low-pass cutting portion for cutting out a predetermined low-frequency component contained in an electrical signal outputted from a first light detector or an electrical signal correlated to its electrical signal and a second low-pass cutting portion for cutting out a predetermined low-frequency component contained in an electrical signal outputted from a second light detector or an electrical signal correlated to its electrical signal, which precede a difference value calculation portion. The difference value calculation portion calculates a difference value between an electrical signal which passes through the first low-pass cutting portion and an electrical signal which passes through the second low-pass cutting portion.

Abstract: A metal surface inspection device for metal rings of a Continuously Variable Transmission (CVT) V-belt which does not perform excessive detection of mackerel skins as a detrimental manufacturing flaw. This task is achieved by providing an “integral value calculation portion” for calculating an integral value of a difference value and a “difference value correction portion” for correcting the difference value in a decreasing direction as the integral value increases. When mackerel skins contained on an inspectable surface are detected the output (integral value of the difference value) of the integral value calculation portion increases. Accordingly, the difference value is corrected in a decreasing direction which enables the operation to control the signal of the mackerel skin portions and threshold values are not exceeded which prevents excessive detection.