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. 27, 2001
Filed:
Nov. 24, 1999
Lester Yeakley, Esters Park, CO (US);
Storage Technology Corporation, Louisville, CO (US);
Abstract
A voice coil linear actuator includes a bobbin connected to a voice coil, a center pole piece, a main magnet, and an outer pole and housing. An auxiliary magnet is constructed and arranged for attachment to the center pole piece such that the center pole piece is sandwiched between the auxiliary magnet and the main magnet. The main magnet has a first magnetic polarization (e.g., North) adjacent to the center pole piece at a first end of the main magnet. The auxiliary magnet has a second magnetic polarization (e.g., North) adjacent the center pole piece, such that fringing fields from the auxiliary magnet substantially cancel fringing fields from the main magnet. Consequently, substantially all fringing fields from the actuator are substantially contained with the actuator. Fields at the magnetic head in a tape drive unit are less than about five Orsted. A non-magnetic spacer can be coupled to a second end of the main magnet to alter the force exerted by the bobbin as a function of current through the winding, such that the actuator can replace existing actuators in form, fit and function, though with improved performance.