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:
Jul. 21, 1981
Filed:
Jul. 24, 1978
Douglas J Hennenfent, Minneapolis, MN (US);
Robert A Johnson, Minnetonka, MN (US);
Allan L Holmstrand, Bloomington, MN (US);
Magnetic Peripherals Inc., Minneapolis, MN (US);
Abstract
A magnetic transducing core having a transducing face defined by planes whose surfaces comprise substantially parts of ferrite grains, and a method for producing this core. The method involves proper selection of the grit size and binder of a diamond grinding wheel, machining its sides to precise parallelism with each other, mounting it on a highly accurate air bearing, rotating it at high speed, and feeding a work piece ferrite bar from which the core is cut into the rotating wheel. These techniques prevent axial run-out between the edge of the cutting portion of the wheel and the work piece greater than 2.5 microns. A preferred embodiment includes a high pressure jet of coolant impinging on the wheel just ahead of the cutting interface.