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. 19, 1991
Filed:
Jul. 19, 1989
Frank H Grimes, Athens, GA (US);
Eugenius S Hammack, Athens, GA (US);
ABB Power T&D Co., Inc., Blue Bell, PA (US);
Abstract
A method of making a product for use in fabricating a low-loss core of a transformer. The core is composed of a web of amorphous metal of small thickness. In forming the product, the web is wound into an annular spiral structure on a circularly cylindrical mandrel. The structure is removed from the mandrel and collapsed into an approximate figure '8' shape and groups of cuts are produced in the upper collapsed surface of the figure '8'. Each cut defines a step of a group. Each step has a number of turns of the web and each group has a number of steps. The steps of each group are offset in a succession along the structure and penetrates progressively into the structure. Successive groups extend progressively inwardly throughout the structure. The cuts subdivide the structure into separate strips. The strips are wrapped in a spiral to form a lapped spiral structure onto a second circularly cylindrical mandrel of smaller diameter than the first mandrel. In wrapping the steps of each group, the ends of each step are lapped and the inner end of each step forms a butt joint with the outer end of the immediately preceding inner step.