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:
Jan. 29, 1991
Filed:
Jul. 25, 1988
Applicant:
Inventors:
James D Jackson, Kidderminster, GB;
Derek E Morgan, Malvern, GB;
Assignee:
Micropore International Limited, Worcestershire, GB;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01C / ;
U.S. Cl.
CPC ...
29615 ; 29616 ; 29446 ; 219546 ; 219552 ; 219553 ; 338296 ; 338333 ;
Abstract
A coiled heating element is manufactured by providing a coiled element of bare resistance wire in which the coil pitch is not greater than twice the cross-sectional dimension of the wire. The element is stretched by an amount permitting recovery to its original configuration and an electrically insulating particulate material is applied to the stretched element. The stretched element is then allowed to return towards its original configuration thus trapping particulate material between adjacent coils of the element and the element is heated so as to oxidize the surface of the wire.