Inspection method for sealed package

Abstract

The invention provides an efficient inspection method for inspecting a hermetically sealed package for pinholes, in which when a hermetically sealed package whose contents such as electrically conductive fluid or food are covered with an electrically insulating film is inspected for pinholes by using a high voltage, the inspection can be achieved with an extremely simple procedure while fully preventing occurrence of misoperations due to the atmosphere such as humidity during the inspection. In a hermetically sealed package in which contents 1 such as electrically conductive fluid are covered with an electrically insulating film 2, an electrical conductor 4 derived from a voltage output terminal of a DC high voltage power supply 6 is put into contact with or proximity to a side face portion 31 of the hermetically sealed package, by which the contents 1 in the hermetically sealed package 3 are electrified. Next, a lead wire 8 is connected to a connecting terminal 5a of an electrode 5 put into close contact with or opposed proximity to an inspection-object portion 3a of the package 3 where pinholes are most likely to occur, and the lead wire 8 is grounded. Then, a discharge current derived from the inspection-object portion 3a that flows only when a pinhole is present is detected by a discharge current detector 7, by which the presence or absence of a pinhole is detected depending on the presence or absence of the discharge current. In this procedure, the inspection can be made by placing the package on a support electrode derived from an AC high voltage power supply and electrifying the contents.

Dependencies are inferred from the claim text.