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:
Sep. 10, 2002
Filed:
Jun. 01, 2001
David C. Brown, Northborough, MA (US);
Michael B. Nussbaum, Newton, MA (US);
Felix Stukalin, Framingham, MA (US);
GSI Lumonics, Corporation, Billerica, MA (US);
Abstract
A reciprocating rotary action actuator consisting of a rotor and stator that can be added to a bi-directional rotary motor or galvanometer scanner, where the stator has a ring magnet and a pair of soft iron pole pieces that concentrate the flux of the ring magnet into a concentric set of narrow, uniformly spaced, axially oriented, magnetic flux fields intersecting the rotor's field of travel. The rotor has small permanent magnets embedded in the periphery of a nonconductive, nonmagnetic rotor core. The rotor magnets have the same number and spacing as the stator's magnetic flux fields. The magnet poles are oriented opposite the flux fields of the stator pole pieces, so that upon rotation, the rotor magnets encounter the stator flux fields at each end of rotor travel, creating an opposing force that reverses the angular direction of the rotor with minimal requirement for actuator current and generation of thermal losses.