METHOD FOR TESTING PRODUCT FOR AIR TIGHTNESS Russian patent published in 1994 - IPC

FIELD: automation. SUBSTANCE: covariant function r(t) of acoustic vibration sound of product is measured during normal conditions of operation. Values of covariant function in conditions at time of testing are measured with given step, and parameters of resulted covariant function are compared to parameters measured during normal conditions of operation. When difference of values are out of given limits then signal of possible loss of tightness. Loss of tightness is detected after three subsequent signals of possible loss of tightness. EFFECT: improved detection of loss of tightness by parameters of acoustic vibration sound in low frequency band. 1 dwg