Inspector for equipment with sound or vibration

Abstract

Abstract PURPOSE:To enable accurate detection of deficiency even for an intermittent defective component where the frequency spectrum from an object to be inspected varies instantaneously by determining the variation with time of the frequency spectrum in terms of frequency components of the spectrum to be compared with a reference value. CONSTITUTION:A noise of a motor 1 is taken into a frequency analyzer 10 through a microphone 2 and an amplifier 3 to apply a spectrum A to a standard deviation computing unit 20 corresponding to the noise. The computing unit 20 determine a standard deviation within a fixed time in terms of frequency components of the spectrum A and a standard deviation vector E in terms of frequency components is applied to a differential device 11. At the same time, a signal (a reference vector F) of a reference memory 12a is applied to the differential device 11 with which a deviation obtained by subtracting the reference vector F from the standard deviation vector E is applied to an totalizer 14 through a non-negative circuit 21. Deviation portions are totalized with an totalizer 14 which provides a total sum G to a discriminator 15. The discriminator 15 compares the total sum G with the set value and judges that the motor works well when the total sum G is below the set value. It judges that the motor is poor in its nature when it exceeds the set value.

Inventors

• 👤 Toshio Takenaka
• 👤 俊夫 竹中

Bibliographic Details