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:
May. 17, 1994
Filed:
Nov. 18, 1991
Norio Yuki, Kanagawa, JP;
Nippon Mining Co., Ltd., Tokyo, JP;
Abstract
A laminated magnetic core is characterized in that core-forming thin sheets each having a surface roughness such that the maximum height Rmax is at least 1 .mu.m are laminated together with a sheet-to-sheet distance of 2 to 10 .mu.m, desirably 3 to 6 .mu.m and that at least a part of protruded portions of the opposite roughed surfaces is diffusion-bonded to each other at the interface between adjacent thin sheets. The laminated magnetic core may have innumberable voids present at the diffusion-bonded interface between the adjacent thin sheets. This invention further provides a method of manufacturing a laminated magnetic core comprising the steps of providing a plurality of core-forming thin sheets each having a surface roughness such that the maximum height Rmax is at least 1 .mu.m; laminating and bonding said core-forming thin sheets one upon another through an organic adhesive, desirably at a sheet-to-sheet distance of 2 to 10 .mu.m; punching out a block of a given shape from said laminated and bonded core-forming sheets by a press; and thereafter magnetically annealing the block while decomposing and vaporizing said organic adhesive to effect diffusion-bonding at the interface between adjacent thin sheets of the block lefting innumberable voids at the interface.