THERMOGRAPHY-BASED METHOD FOR DETECTING DEFECTS IN SEALS COMPRISING CONDUCTIVE INNER-SEALS

摘要

The present disclosure provides a method for detecting hot sealing defects in a container while it is being conveyed along a process line. The method is particularly suitable for vessels covered with cap liner and sealed with inner seal. The method uses a high frequency train that generates an eddy current in the inner seal (e.g., by a high frequency thermal induction unit), thereafter being sensed by an IR imager of radiation emitted from the conductive inner seal, The sensed IR image data is generated. The sensing may include: (i) a time window of a sensing session between 50 msec and 300 msec while the container is being carried through the FOV; And (ii) a detection range of a wavelength spectral region of 2 [mu] m to 6 [mu] m; As shown in FIG. The IR data is then processed to produce output data indicative of the presence or absence of at least one defect in the sealing of the container by the inner seal.