The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 28, 1981
Filed:
Jun. 29, 1979
David S Knudsen, St. Louis, MO (US);
Other;
Abstract
A container having a generally rectangular rim surrounding its opening is closed by a foil membrane that extends over the rim and is sealed to the rim by inductively heating it. The membrane does not correspond in configuration to the rim, but instead its side and end margins curve away from the sides and ends, respectively, of the container rim, so that the peripheral margin of the membrane is located closer to the container rim at the corners of the rim than at the sides or ends of the rim. The foil of the membrane is coated with a resin bonding material, and when the membrane is placed in a rapidly oscillating magnetic field, its foil is inductively heated throughout the entire area that overlies the rim, thereby rendering the bonding material plastic and establishing a uniform bond between the rim and membrane. In contrast, a membrane having the same generally rectangular configuration as the rim will bond to the sides and ends of the rim, but not to the corners without overheating the membrane, since a membrane of that configuration does not heat uniformly in an oscillating magnetic field.