Testing container seals
AssigneeBenthos, Inc.
InventorWilliam H. Hulsman
Life of this patent
Estimating the term…
Abstract
Leak detector for use in detecting defective flange-shaped seals between lid and body portions of a package. A pressure chamber is provided for isolating the external edge of the seal and applying test pressure thereto. Containment of the pressure chamber includes sealing pressure applied mechanically to the flange-shaped package seal during testing, but this sealing pressure does not affect seal testing because it is appropriately limited by a self-compensating biasing of the mechanical seal.
Claims28
A method for detecting a leak in a defective seal of a package having an edge seal that is formed by a bond between overlapping edge portions of walls of said package, one said wall having a flexible portion that changes shape as the volume in said package changes, said method comprising
- providing said package,
- applying a first pressure to exposed outer edges of said edge portions of said walls and a different second pressure to said flexible portion, and
- detecting deflecton of said flexible wall in response to flow of gas through a leak in said edge seal between said overlapping edge portions.
Apparatus for detecting a leak in a defective seal of a package having an edge seal that is formed by a bond between overlapping edge portions of walls of said package, one said wall having a flexible portion that changes shape as the volume in said package changes, said apparatus comprising
- means to apply a first pressure to exposed outer edges of said edge portions of said walls and a different second pressure to said flexible portion, and
- a deflection detector to detect deflection of said flexible wall in response to flow of gas through a leak in said edge seal between said overlapping edge portions.
Apparatus for detecting lateral leaks in defective seals of a package of the type wherein flange seals are formed by at least one lateral bond between (a) a flexible lid part of said package and (b) a outwardly-flared flange of a container part of said package, said apparatus having
- (a) means to support said container at a first pressure;
- (b) means to isolate the entire outer edge of said flanged seal from the rest of said container, supported at a first pressure;
- (c) means to apply gas at a second pressure to said outer edge of said flanged seal;
- and
- (d) means to detect the deflection of said flexible lid in response to flow of gas through said lateral flange.
A process for testing leaks in a flanged seal between a flexible lid portion of a package and an outwardly-flared flange of a second part of said container said process comprising the steps of
- (a) applying test pressure to the lateral edge of said flanged seal while maintaining the remainder of said package at a different pressure from said test pressure;
- and
- (b) measuring the displacement of said lid as a criterion of a leak in said lateral seal between said lid and said flange.
Dependencies are inferred from the claim text.