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:
Feb. 26, 1985
Filed:
Aug. 16, 1982
Joshua Benin, Newark, DE (US);
Robert P Luoma, II, Newark, DE (US);
E. I. Du Pont de Nemours and Company, Wilmington, DE (US);
Abstract
An electric heating element for sterilely cutting and welding together a pair of thermoplastic tubes transversely of the axis of each tube includes as an outer layer a folded sheet of a metal, such as copper, aluminum, silver or gold, having a thermal conductivity of at least about 173 watts/m.degree.K at a thickness of 0.10 mm and a tensile yield strength of at least 34.times.104 kPa at a 0.10 mm thickness. A resistance heating element, preferably having a positive thermal coefficient of resistance (PTC), in the form of a resistor of stainless steel or the like is disposed inside the fold of the metal sheet and a layer of dielectric adhesive, such as an epoxy or acrylic adhesive, stable to about 260.degree. C., is disposed between the inner surfaces of the metal sheet and the resistor to insulate the resistor from the folded sheet and bond the resulting structure together. The folded edge of the metal sheet forms the melting edge of the heating element. The heating element has a thickness of from about 0.13 mm. to about 0.76 mm.