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. 30, 1995
Filed:
Feb. 01, 1994
Hemant K Mody, Rochester, NY (US);
Eastman Kodak Company, Rochester, NY (US);
Abstract
A linear motor of the type used to control the radial position of a write/read transducer relative to a rotating data storage disk comprises an elongated tubular-shaped permanent magnet which concentrically surrounds and is spaced, by an air gap, from an elongated pole piece of highly permeable material (e.g. steel). A selectively energizable coil, concentrically arranged between the magnet and pole piece, is adapted to move axially in response to an applied current. According to the invention, the pole piece supports a plurality of 'shorting rings' made of high conductivity, low permeability material. The shorting rings are embedded in the pole piece so as to be coextensive with the surface thereof. The spaced shorting rings function as a 'shorted turn' which operates to reduce the rise time of current applied to the coil without significantly reducing the magnetic flux in the air gap through which the coil is linearly driven.