Method and device for determining the end of the replacement of air by another gas in insulating glazing

摘要

In the case of gas exchange in insulating glazing, by which the air at first present in the insulating glazing is replaced by a gas which is denser than air, the time at which the denser gas has displaced the air from the insulating glazing is established by producing an acoustic oscillation of essentially constant wavelength in the gas flow leaving the insulating glazing and observing the drop in the tone pitch which occurs as soon as the oscillation occurs in the denser gas instead of in air.