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:
Aug. 31, 1976
Filed:
Apr. 07, 1975
Albert E Paladino, Needham, MA (US);
Paul F Weihrauch, Newton Center, MA (US);
Raytheon Company, Lexington, MA (US);
Abstract
A method of making an integral toroidal magnet comprising the steps of compacting suitable magnetic powder material into a toroidal shape while subjecting it to a particle aligning magnetic field, hot pressing the compacted powder toroid in a confining die at a temperature and pressure sufficient to cause shrinkage of the toroid in the axial direction and provide a packing density greater than 93% of the theoretical maximum value and substantially unidimensional shrinkage, heat treating the toroid at a temperature sufficiently higher than the hot pressing temperature to achieve an enhanced crystallographic alignment equivalent to the alignment obtained by sintering, annealing the toroid at a temperature sufficiently lower than the heat treating temperature to provide a magnetic coercivity similar to the coercivity achieved by annealing after sintering, and magnetizing the heat treated toroid in the direction of crystallographic alignment.