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:
Dec. 30, 1986
Filed:
Dec. 27, 1984
Frank M Willis, Wenonah, NJ (US);
E. I. Du Pont de Nemours and Company, Wilmington, DE (US);
Abstract
A heating element for sterilely melt-cutting and welding together a pair of thermoplastic tubes transversely of the axis of the tubes includes an outer folded metal sheet, such as copper, aluminum, silver or gold, an electric resistance heating element of stainless steel or the like disposed inside the fold of the sheet and a dielectric adhesive disposed between the inner surfaces of the sheet and the resistor to insulate the resistor from the sheet and bond the structure together. The folded edge of the sheet forms the melting edge of the heating element. Vent channels within the adhesive and along at least one unfolded edge of the metal sheet are provided to vent entrapped gas from the element during heating. The channels have a predetermined cross-sectional area and length such that the pressure driven flow of entrapped gas passing through the channels is greater than the pressure-generating vaporization rate of the trapped gases to prevent the entrapped gas from reaching pillowing pressure within the heating element.